>without a UX that abstracts away the siloed nature of federated instances

Can you be more specific? Only thing I found missing was "Quote Posts" and almost everyone seems to agree that it was the right decision to make.

> will prevent Mastodon from ever growing beyond a small niche

And its not a good thing? "There's an instance for everything" is fast becoming an reality, Let those instances be small as its managed by volunteers;

There's no need for everything to grow into a democracy destroying scale, Especially Social Media platforms.