That's not something that I have any interest in, but I'm not opposed to it as I know other people have asked about it.

A very quick peruse of the Mastodon issue tracker came up with information about this on the ActivityPub level (albeit in an old toot): https://mastodon.social/@reiver/113668493283013849 and someone kindly rounded up similar feature requests here: https://github.com/mastodon/mastodon/issues/33098#issuecomme...

I like the idea of it not being related to a platform or implementer, but baked into the spec ala a feature of ActivityPub.