It does appear that there is some consolidation in the group space. Pixelfed and Mastodon both seem to be converging on the Smithereen implementation, and that's one of the implementations we support. Another handful of projects are converging on "just use mentions" and we support that as well (but only for public groups). We're probably going to see some issues about cross-platform leakage of private group content because we can't agree on whether privacy is an attribute of a post or of a conversation (with the same polarised debate as surrounds tabs vs. spaces or vi vs. emacs or AGPL vs. MIT). But this was always going to be a problem.

Anyway, consolidating into two competing camps is much better than where we began.