If I don’t remember wrong we could connect and link our handles with Discourse user back in early days of the plugin. It disappeared at some point, or changed its functionality.
But nowadays we have to make an ordinary link to show an account in web-style. And yet changing handles to <a href> links in federated categories is bad policy AFAIK.
If I stay in meta things we have some issues with how ActivityPub of Discourse is working (Mastodon only, the way how topics are shared via category/tag, error is the log etc.) but I don’t bother ask any more. Basically any ActivityPub related questions won’t get reactions from CDCK direction. Perhaps it is because of ActivityPub isn’t part of Discourse main functionality, perhaps it is too rarely used or perhaps it is too difficult and expensive task to solve out without building a forum beeing a thoroughbred (mastodon) instance.
What ever but the situation is I can’t rationale on Mastodon side why any Discourse forum shoul use the ActivityPub plugin. Using WordPress as a bridge between Discourse and federated world is a better solution, but then connection to Discourse direction vanishes.
My point is question if a handle can be a proper link as used in the web is not the most important question, but is ActivityPub plugin totally abandonded.