We can't effectively block corporate injections, unfortunately. The admins of large hub instances are just of the opinion that bigger is better, and that more is more. They've been excited by the prospect of, I don't know, legitimacy or something, for a while now.
The result is going to be the network... not fracturing, per-se, but significantly restructuring itself. Big instances will get sucked into Big Social's halo, and be like the suburbs to Meta's or Tumblr's metropolitan centres. Smaller instances will end up as the exurbs. Content will flow quickly between metro and suburban spaces, and trickle across suburban spaces between the metro and exurban spaces. And which Fedivesre site you choose to use will end up mattering even more than it does now.
Right now, there's speculative reason to believe that Meta's offering up incentives to big instance admins. Those incentives will ultimately result in Meta owning them by proxy. They'll be client kingdoms, to mix metaphors, working on Meta's behalf, but getting relatively little in return for it.
I think Reddit moderators probably have a good idea about how they'll ultimately end up feeling.