ActivityPub unfortunately does need some work, and there's drama about properly following the protocol and not extending it with non-standard stuff that then breaks things when federating with stuff outside the given application.

I'm optimistic, but I'm also making sure not to put too much of a stake in it, as it may eventually become an inferior system when compared to some future hypothetical standard.

And other standards like diaspora and ATProto, are around, and seeing use.