Gregory's ServerReply Collections have not yet really reached the centre of the #Fediverse. Among other things, moderation aspects play a role here (see FEP-7458 or FEP-5624). But in principle, they offer a wonderful opportunity to maintain consistency in discussion threads in the Fediverse.
Smaller instances in particular often lack reactions to content published in the Fediverse. In principle, this is not a bad thing. Nevertheless, it makes sense for both servers and clients to be able to retrieve a complete comment tree in some scenarios (possibly at the request of a user).
To this end, we have submitted a first draft in a pull request to the Upstream #ActivityPub plugin for #WordPress. In this case, we benefit from the already existing comment management of the WordPress core and only list approved comments in the replies collection.