Charlaquin
Goblin Queen (She/Her/Hers)
Also, like... I don’t think the “most of them were probably test builds” argument really helps the case against most players not using Feats. 5e is not so complex that a test build is necessary if you aren't planning to use Feats. I would imagine, then, that most test builds would have them.D&D Beyond controls for builds not being used, and controlled that way has a sample size of tens of Millions of characters.
Even granted maximum pessimism about Beyond's data, and we assumed that all D&D Beyond character builds were tests, it would remain significant that 3 out of 5 of the tens of Millions of such builds didn't bother with Feats still.