I think Fediverse mobile apps - just focued on small groups of friends and family from a a UX perspective, where all posts are by default "limited" and that use the group functionality being cooked up by @dansup and Mastodon... should definitely happen.

No need to have giant silos own that space that is by definition local and should be private.

https://www.androidpolice.com/tiktoks-parent-company-launches-new-app/