At this point I just feel bad for people who still try to engage with transferring. It legit feels like there's some new obstacle almost every game that releases, all while dealing with a shitty content-bereft overpriced app. Champions should make things more bearable, but still

Call it unpopular, but I have never seen any reason to move *back* my pokemon. After a game went out of CG, i usually just moved everything to Bank/Home and either uninstalled that game or only kept around the bare minimum for breeding back when transfer moves were a thing.
Even in the case where I'd want to replay a old game for nostalgia or something, I'd be starting over, so the "transfer back" wouldn't have been relevant anyway. So I don't quite get all this attachment to "being able to move pokemon back" and I honestly do wonder how many people even *used* that function.
(The only reasonable use for it I could see would be if you acquire a old game way after it came out, and wanted to fill the pokedex for some reason, es for getting the paradoxes or bloodmoon in SV I guess, but it's such a specific scenario I still struggle to see it)