They were /not/ in favor of the proprietary Motif desktop environment, nor the (at the time, non-FLOSS Qt library dependent) KDE (C++) environment, hence the FSF creating the GNOME (C) environment. "...GNOME and KDE will remain two rival desktops, unless some day they can be merged in some way. Until then, the GNU Project is going to support its own team vigorously. Go get ’em, gnomes!"
https://www.linuxtoday.com/developer/stallman-on-qt-the-gpl-...
Related - the BSD License:
> ...a quote directly from Bostic himself. I asked him about it, after reading this FSF page: "People sometimes ask whether BSD too is a version of GNU, like GNU/Linux. The BSD developers were inspired to make their code free software by the example of the GNU Project, and explicit appeals from GNU activists helped persuade them..."