However, it's frankly foolish to think it's going to take over. I know I can't convince any of my friends to use Mastodon, or anything ActivityPub-related. It's not because it's too complicated (though for some reason people still think that's what's holding it back), and it's not because it needs more development time, it's because nobody uses it. People are stuck on Twitter, Facebook and Instagram because they're designed to retain you, no matter the cost. Every second you spend browsing is designed to lock you in further, generating more ad revenue. The social structure of these platforms is meticulously designed to make people feel like they've got more stake in the platform; you follow celebrities to stay 'in' on the gossip, you follow smart people in some faux investment of intellectual capital, and you follow successful people because you think that basking in the starlight will impart something valuable to you.
Of course, none of that happens. At the end of the day, it's just people scrolling through brief text/video blurbs where they retain little to nothing from their interaction, just adding more lubrication for the money-making machine to chew through. Oh, and if any of these smaller, federated platforms do gain traction, they're going to have to fight off billions of dollars in vested interest to keep them out of the game. The big influencers will stay in the pockets of the big players because they treat them well. The big players will ramp up their marketing campaign, acquire newer platforms or create their own spinoffs that diametrically oppose a free internet. There's always a bigger content silo to be made, and they're the ones with the resources to do it.