There's a general, well founded, distrust of meta. Theres a general theory going around that they will embrace, extend and extinguish the fediverse. It will ride the wave of federation then when it gets large enough it will defederate or add some dumb feature that will break all compatibility. The problem with this strategy is it will bring them in front of a court for anti-conpetitive behavior, just like what happened to Microsoft every time it tried to do this, and possibly break up the whole company as instagram might get shaved off too. There's a reason Google doesn't try to do this with chrome or gmail, they learned it's a bad strategy from Microsoft. The reality is the fediverse as it stands right now is a blip to meta, a blip they can point to and say they aren't a monopoly, but just a blip, not some radical existential threat that needs to be destroyed.