I don’t see any downside at all if it’s layered on top of some other (very capable) keyboard-driven UI that can do all the same things.
The downside is that no existing tech company has enough self-control to actually keep these kinds of recordings private.
There was a clearly stated reason for these removals, but it is a reason that does not appear either in lemmy.ml's rules list nor on the page that you listed.
There were additional moderator actions citing the same "orientalism" reason that occurred while I was writing the post:
Screenshot of lemmy.ml modlog
It is my opinion that this is a significant rule to leave unstated.