Most people who use hashtag-only changeset comments do not do so because they think it is cool but because someone else - or a piece of software - told them that’s the way to go. I don’t think we’d be curtailing anyone’s free expression if we ask them to write human-readable comments; even if hashtags were somehow the lingua franca of a specific generation, a sentiment I don’t agree with, that would not be a valid reason to use that single-generation language in a multi-generation project like OSM.
I’d also politely request that this discussion not be derailed by whataboutism - “if you are against X then you must also be against Y and HERE’S MY ARGUMENT WHY BEING AGAINST Y IS BAD”. I have not suggested to reject contributions from users of software that forces them to use auto-generated tags and therefore I am loathe to discuss how useful (or not) they are in this context.