On the other hand, I don’t think that really applies to GNU/FSF.
>willingly ignoring the egoist telekommunist branch
Look. None of the communities are exactly homogenous in the first place. Moreover, even if you say “Open Source” you’re not necessarily an open-source advocate (like with Perens). Some people (wrongly) think that saying “Open Source” is less ambiguous but that doesn’t mean they aren’t still libre software supporters. Some libre software supporters may have personal grudges against RMS or FSF. That also doesn’t make them not libre software supporters. Yes, many libre software supporters support RMS and FSF because they have solidarity with them but it isn’t necessarily the case. There’s a lot of gray area but the point is made about the generally accepted ideologies rather than more specific cases. Thinking that either of these communities are homogenous is misguided.