This is fool talk. Jan 6 and the entire MAGA movement to a first approximation is a grift. It is precisely the opposite of the French Rev. It is the selling of cake in the form of hats and delusion.
FB was allowing this messaging. Twitter not so much, T was much more aggressive at moderation.
Removing FB is a completely different issue for an app store than Parler, for obvious reasons. Parler also of course was funded by sources that were in US terms problematic.
Apple is going after FB in more structural ways. Google tried, but failed. FB is an issue for DoJ now.