@phoe is notabug.io federated using ActivityPub though? There are heaps of non-AP Reddit-a-likes, including lobste.rs, Hacker News, #SteemIt, #Minds, and others:
https://www.makeuseof.com/tag/7-awesome-reddit-alternatives-need-check-today/
But AFAIK only the ones @switchingsocial listed are implementing AP