I really don't know if you could.
Having seen OpenAI's trajectory of becoming a for-profit and not being "Open" in any serious sense of the word, I genuinely think market forces can absolutely pry open any chest they perceive as containing gold.
My personal conclusion is that you genuinely have to deal with human beings. Take federation for instance: we can try to decentralize these things and make an incredibly solid system, but we still depend on people coming to the realization that this is a good idea and adopting it for their personal/professional internet use.
Now I'm wondering if there such a thing as a decentralized private company? I can't think of anything beyond having subsidiaries in different countries, but that still requires a parent or at least a main point of contact in the form of the owner. So we're back to humans.
It's worth at least giving it a try. My opinion is far from consensus. P2 is for the most part just a retelling of the Haruspex route with (VERY welcome) improvements, so you really won't be missing out on anything plot-wise.
I've heard people say it's better to start off with Bachelor because it's more grounded but I really don't think it's necessary. You're just gonna learn about some of the more exotic aspects of the universe before the more mundane ones.
To chime in on the user creation thing:
I think it's a natural part of decentralization that it's harder for a single instance to get big enough to be the "go-to" for general users.
Having said that, I also think this will naturally happen over time. As long as the mechanical aspects of sign up are simple, it's just a matter of users of a given instance to promote their instance.
World events also always play a role in encouraging a move to freer waters. Look at what happened with Mastodon and Bluesky (though Bluesky imo is just a big snooze button on a blaring alarm)
Nothing but end-times news these past couple of weeks.