That's been one of my mottos for a long time. I've always been frustrated with D&D as it was written in the 70s and 80s. But in the end, I realized that these were details of the rules, not the core of them. I mean, sure, there were a lot of rules that I didn't love, like non-weapon proficiencies, and weird saving throws, and THAC0 and crap like that, but as a whole, with minor changes, the core of the games were pretty good. Especially as the modern retroclones have cleaned up some of the worst problems that they had. This is where I align, I suppose with the OSR.
However, the flavor was all wrong. The thief should be a much more useful class, and the mechanics of it were always terrible. The magic system, spells, and magic items were all unlike anything I'd really read in fantasy before, and I never liked magic (although to be fair, apparently Gary Gygax didn't really like it much either. That said, his design for magic-users was always bad.) Clerics were not actually much of a fantasy archetype, and the way healing was handled by "divine magic" was always unsatisfying. Many tropes were obviously cribbed from high fantasy, especially The Lord of the Rings, and some others had obvious influences in sword & sorcery, but because Gygax's background was wargames, neither of those influences felt very much like the fiction; they were too "gamified" if that makes sense. D&D quickly turned the wrong direction; the rules and mechanics of OD&D were blundering through trial and error into figuring out what worked, but it was on the right track in terms of what the game was about and how to play it, for the most part, but as it accreted more and more rules, edge cases, and the focus on dungeon crawling, not to mention the detritus from wargaming that it still couldn't conceive of leaving behind, I got more and more disillusioned with D&D specifically. It failed to deliver on the implicit promise inherent in the hobby that a fantasy literature fan like myself saw in it. I didn't want to play a tactical wargame, I wanted to collaboratively and improvisationally go through something that resembled the fantasy literature that I loved. By the mid-80s, ironically as the Hickman Revolution was remaking the hobby in some ways into something that better matched my stated goals, I got tired of D&D and wondered what else going on in the hobby would better suit my interests. Well, to be fair, I was also busy doing other things a lot in the second half of the 80s, as I was in high school and gaming was one of those things that I had a fringe interest in, but didn't really spend time or energy on anymore at that point. But I did keep track of a few other things going on in the hobby, or in adjacent hobbies. I checked out MERP and the Fighting Fantasy Gamebooks, for instance, and spent at least some time looking at Star Frontiers, Gamma World, Top Secret S.I. and a few other games (mostly the other TSR games, because they were the most readily available.) I was passingly familiar with Call of Cthulhu, Runequest, Champions, and more, although passingly familiar and actually familiar were probably miles apart. It was later in the early/mid 90s that I came back to gaming, and at that time, I was deliberately avoiding D&D. Instead, I got interested in what White Wolf was doing, I discovered a college friend who had Top Secret SI kicking around, and I got into some older Traveller stuff. I didn't regain any interest in D&D until 3rd edition in 2000.
I was always a bit skeptical of the Hickman Revolution and the switch from Classic to Trad style which seemed to have happened. Although I consider myself a trad guy, it was immediately obvious what the excesses of trad would be and how they could be extremely detrimental to a game. Player agency is still paramount, and pre-written campaigns or even modules with plots would easily devolve into railroads that nobody wanted to play, because just write it as a freakin' book and let me read that instead, already. The improvisational and collaborative elements of RPGs were always core to their appeal, and minimizing those was never going to go well. The risk inherent to the characters was also part of the appeal, and what made it exciting; another excess of the trad style is crafting stories or at least potential stories around the characters, which makes everyone much less willing to see them put in any significant risk. A perhaps unintended side effect of this is that the primacy of "my precious character" from a plot standpoint, also, or perhaps in parallel, draws them inexorably towards power fantasies and over-powered superhero characters.
Meanwhile, as the style changed, the mechanics did not, which only frustrated me all the more, as what I wanted D&D to do and what it actually managed to do were all the more divorced, in many ways.
Although the flexibility inherent in the WotC editions of D&D, starting with 3e which I played the heck out of it for many, many years allowed me to get more of what I wanted from the game, it was also not designed with what I wanted in mind, and I gradually got more and more frustrated yet again with the game. The strategy of player-facing products was interesting for a while, because it allowed for a great deal of setting development through mechanics... at least when it was done well, although it didn't take long for that to become quite boring and focused on mechanical dickering and build strategies rather than actual "fluff" concerns that were interesting.

When 4e came out, I didn't have any interest in adopting it, even though from a lore standpoint, it actually did more of what I wanted... it's just that by that time, it didn't do enough. I was clearly ready to move on from the D&Disms, and D&D was still quite conservative, at least in the sense that it failed to be anything terribly different than it used to be. Ironically, many conservative (and I mean this in regards to lore and expectations of the game; not socially or politically, of course—although I do think that there is at least some correlation between the two) thought 4e was a step too far; to me, it wasn't enough to interest me. And many of the other things it did, like focusing on character builds and long, drawn out combats, were exactly the opposite of where I wanted to go. Pathfinder, although different mechanically, also followed that same directive. 5e too, as near as I can tell; the idea that it's considerably streamlined compared to 3e or 4e only makes sense if you operate in a world where D&D is the totality of the RPG market. 5e is full of compromises; it's basically a slightly streamlined 3e, in terms of character builds, at least, but with pretty much the same unlikeable combat system, and plenty of additional complexity in areas that don't interest me.
So, I've finally come around to being more positive towards the OSR, which for many years—quite honestly—kind of irritated me, due to the spergy behavior of some of its most vocal adherents, and it's trumpeting of classic playstyle (which gradually evolved into the OSR playstyle, which has some similarities, but also some significant differences). I still don't really want to play an OSR game, but I think starting with an OSR chassis, or OSR-adjacent chassis, at least, and modifying it to be less overtly D&D-ish and more able to replicate the kind of implied setting that I want is where I am, in most respects. It's also very much worth pointing out that I'm still an old-fashioned guy, but firmly in the trad camp, although as noted above, with some long-standing skepticism of its excesses. Systems that are designed with trad style in mind rather than classic could do some things differently than the OSR did, which went from being specifically to cloning the old systems, to furthering the OSR playstyle. Maybe you could call me paleo-trad; trad but with a firm grounding in old fashioned classic play. I left classic because I didn't like it and trad promised what I always wanted RPGs to do, but classic also created many of my tastes, or at least strongly informed them.
So, I'm old-fashioned, but not old school. I'm more comfortable going back to an old school chassis and modifying it to be more what I want than I am starting with a modern chassis. Not that there hasn't been some pretty cool and interesting developments system-wise, because there absolutely have been. All three of the modern editions of the game brought some cool new innovations to the table. But mostly, I'm not happy playing in an OSR style, even when I prefer to modify OSR mechanics. There are still things about most OSR systems that I don't love, but getting the mechanics into a more "cleaned up" OSR baseline and then variancing based on taste and flavor from there is where I'm at now.
And speaking of being conservative in terms of what I want; holy cow, has fantasy become weird, apparently, in the last couple of decades. Since when is fantasy some weird diversity utopia with animal people and superheroes all over the place?