Yes but those patches had a lot of problems, plus Blizzard didn’t have a backup of any of them, I think they said they had backups of 1.9 or 1.10 forward.
Sure if they went with 1.5 instead of 1.12 we’d have a better AV but we’d also get a bunch of problems on top of that who where fixed along the way and we’d have A LOT of content missing, we’d never get to do Naxxramas for example.