Bell Beakers role in forming modern Europe

I really wish this chart had marked Unetice.  It's curious that the Bell Beaker seems to be extremely close to Corded Ware, but pulling more towards the EEF-like genetics, but rather not as similar to Yamnaya as you'd have expected given the popular theory that it represents the superimposition of R1b Yamnayas over (among others) an earlier spread of R1a Corded Ware.  Looks like that is unlikely after all.

Anyway, the "Beaker Folk" and their role in turning Neolithic Europe into a Bronze Age Europe that resembles much more closely modern Europe is still unclear.  Where did they come from?  Who exactly where they?  What language(s) did they speak?  What was their interaction with the various material cultures with which they seemed to coincide in time?  And where did they go?  Are they the immediate ancestors (for example) of Unetice and additional later cultures, like Urnfield or Villanova?

For example, finding out that only about 10% of the Neolithic Stonehenge builders of England were successful in passing their genetic legacy to later British populations, who are overwhelming sourced to the Dutch Beakers doesn't necessarily mean much if you can't identify who they were.  They are too early to be Celtic, too late to be EEF, and the Beaker origin is hazy anyway (Dutch Beakers, both archaeologically and genetically seem to be most closely related to the Corded Ware subgroup called Single Grave Culture.)