Browser yes, but OS? Rarely, I have issues with Firefox, but never had Chromium not working, too.

It any case, it would be silly to assume services measuring OS popularity would put up such limitations. And more likely than not, people are changing their UA as a work-around on a case-by-case basis than make it a default, since that's gonna cause trouble.

In the last decade, the only time, I actually had to touch the UA is when breaking ToS with curl :D