I’ve seen that some instances have already done it preemptively.
What I would do if I were Zuck is the following: First I’d federate and leech a little bit off the pre-existing community. Then, I’d start buffing out my version. I could outpace the open source team easily if I wanted, adding things like video hosting, that are too resource-intensive for smaller Instances. I’d basically compete in features and polish, which are very important to less tech savvy consumers.
In the meantime, I’d be tinkering with my own Instance, seeing how much more data can be squeezed out of the Fediverse. I’d probably buy some of the largest Instances and assimilate them, just to keep the rest of the space feeling small compared to mine. Let brand loyalty do the rest.
Any time they come up with a new feature I like, I take it. I don’t share mine though, I don’t share anything I’m not forced to. The goal is to cap their growth, basically squashing awareness of them by making sure that when average people think Fediverse, they think Meta. The rest of it is just weird tech hobby junk for nerds.