I feel like it's unlikely to happen regardless of the userbase. Fediverse as a whole seems to have been built on different merits and it's curated by the large corporations, so they won't be coming here with their algorithms and ad-revenue and thirst for profits and engagement.
The biggest difference between Fediverse and the old-school internet websites, like forums and blogs and such, is that Fediverse is relatively easily intertwined; it's an ecosystem that consists of autonomous small-ish communities that get to choose whether and what they share. If you want, you can basically make one account, subscribe to as much shit from the Fediverse as you like, and have it all come to your curated feed (defederation happens, though) - or you can treat it all as separate platforms and have one account for each, with occasional guests hopping by (like you're with d.gs and I'm with feddit.de).
Even if there are platforms that later use the same protocols to try and get some profits, they'll most likely be out of everyone's memory much like Threads (remember that?) because it's just not the same as creating some kind of "everything platform" and have people walled off there to "engage" with rage-inducing content and have them (hopefully) generate ad revenue.
I think we'll collectively figure it out with time and have more specific, yet popular instances, rather than instances trying to be the all-places with communities. Like an instance for memes where communities act as sub-categories or something.
But I maybe wrong, I'm not on oracle or something.