I'm assuming you mean for internet multi not local? That's been a thing tried since remote gaming became viable, some worked some failed, some just built things where lan parties became a thing and told the users to figure it out themselves.

Consoles from the dawn of time have had locked OS and no mods (unless you count things like the game genie/shark systems) so that's nothing new either.

I'll stick mostly to PC myself, but those things aren't unique to the PS5.