As you rightly say, before fb, there were several platforms that competed, but it turned out that on a globally operating, platform economy, the winner takes it all, and thus there is now only fb (and a few others that compete for their niches), a monopolist, that dictates the rules for everyone, this is a possibility, because corps can act globally, but laws are local, eos with a globally set up - binding! - governance , would be able to rebalance this, but is now threatened, to become yet another uninspired chain, with maybe a solid tech base, but that's certainly not an usp for long....
RE: Proposal for an incremental Constitution and Dapp layer governance on EOS