Fair enough, I interpreted your comment:
Steam Deck is almost 1% of the Steam user base. That's pretty crazy for a single model of computer. It's more than all the Apple M1 models combined (including Pro & Max models).
as saying Steam Deck outsold the Apple M1. If you are comparing user bases, MacOS users outnumber SteamDeck users on Steam, but probably are split amongst various Mac models so Steam Deck may be more then M1 Macs. Not sure why that matters, since both are an insignificant part of Steam's business.
Apple has never seemed to be serious about Mac gaming, they're much more focused on mobile games, IMHO. Part of the problem may be, unless a game mirrors the PC version exactly but has an Apple interface, Mac gamers will pan it.
I also suspect it's hard enough to make money with PC games, so investing time and resources in Mac games makes no fiscal sense.