Automata is at 8m now. But I think they announced It alongside the Switch release, so It's probably higher now. Wouldnt be surprised If It was closer to 10m now, thanks to the anime helping out a little.
Wouldnt be surprised If the PC sales were around 2m~ and PS4 around 6m~. The game was (and still is) pretty rough on PC afterall.
A native PS5 rerelease alongside switch 2 could bump the numbers heavily as there are a lot of new players on the market, that never had a chance to play It before. Fix the graphics, add in the cut content and rerelease that shit already.
The issue with Automata is that there's no best way to play It. (Kinda like Rayman 2)
The Switch version has the most amount of content, but is capped at 30fps and looks like crap, the PC version is beautiful with the help of mods, but runs like shit, while the PS4 seems to be the best middle ground so far, but far from perfect.