@evan ActivityPub has a ton of momentum and adoption right now thanks to Mastodon, and I don't think a dev publishing a paper or a toy implementation threatens that. People should publish early and often.
It looks like the biggest adoption spoilers might to be federation wars over moderation policies, followed by inter-instance latency.
Basically, mods have to be made irrelevant; users must be empowered to set boundaries that work for them, are transparent to others, and are enforced broadly.