Once Meta gets their foot in the door, I guarantee they will try to bully the fediverse into doing things their way. Hard pass for me.
Can you give any reasonable by means in which they could do this and succeed?
So much of this stuff just sounds like infeasible conspiracy theories. If, hypothetically, Meta did do such a thing (somehow, still not clear how or frankly why?) all that it would mean is that anyone who disagreed could defederate from Meta, or would be defederated from Meta... which given half the servers in existence seem to want to defed them up front anyway, doesn't seem to make any odds.
It's all just very confusing hearing about these lurid ideas for things Meta could do with the fediverse that simply don't make a lick of sense either in terms of motivation or implementation.