I'm not sure I understand your example. What actual value would M1/aarch64 compiled steam binaries be? Practically all games available on their platform are made for x86 or x86-64. That doesn't seem like something Valve can change. The only reason gaming on Linux is becoming practical is because Vulkan support is maturing and Valve doubled down on getting windows binary compatibility.
I suppose Proton could probably be ported to OSX with enough work. Apple isn't making it easy by refusing to natively implement Vulkan, though. DirectX to Vulkan to Metal conversion on top of x86-64 emulation is just a lot going on. It seems like no one's interested in doing the work to convert DirectX directly to Metal.
Valve's insane corporate structure means its strategic moves are plain as day. They initially went on OSX because it made sense to leave no room for a competing game market to start on Mac and move to Windows.
They've invested massively on Linux and have attacked the problem from two angles in the last ten years because they need to diversify. They can't single-handedly rely on Microsoft for their continued existence. Hence the VR headsets, the Steam Machines, and now the Steam Deck.
They've put zero effort on macOS on Apple Silicon because they would gain nothing strategically, and the percentage of Mac users using Steam is small. The hardcore gamer on a Mac does not exist. We have consoles.
It's not insane for them to be transparent. When Valve depreciated Steam Play for MacOS, they had engineers very clearly spell out the reason: the MacOS runtime is not stable enough for games. They also called this out when depreciating SteamVR for MacOS, it seems less like a "strategic move" and more like a platform limitation.
There's definitely something for Valve to gain by porting Steam to MacOS, after all they did support MacOS with Proton originally. The work required to fix it for modern MacOS is monumental though, and unless Apple sponsors it I see no reason why it would happen. Once they axed 32-bit execution support on Mac, there was effectively no reason to keep supporting the platform anymore gaming-wise. OpenGL depreciations were the icing on the disappointment cake, very clearly Valve was being told to pound sand by Apple.
MoltenVK exists so that would take of Vulkan. Rosetta2 is super efficient, so I don’t see that as an impediment. The truth is, I don’t think Valve cares much about Macintosh. Blizzard doesn’t lately either. Oddly, the trend lines here are weird. MacOS is becoming the “get stuff done” platform, and Linux is becoming a gaming platform, both of which were previously Microsoft’s domain.
WoW64 support was added recently, so you shouldn't need a 32-bit Wine in the near future. This is because some Linux distros are also ditching multilib support on x86.
There are several games I play that are actually natively compiled for M1 (The Long Dark, Disco Elysium). Steam is a very noticeable resource hog on an M1, and I'd presume that's a mix of their UI framework mixing (CEF, VGUI) and lack of Apple Silicon binaries.
> That doesn't seem like something Valve can change.
This is where I'd disagree with you. Valve has all sorts of levers they could pull to encourage ARM builds. One example, they could offer a lower commission rate on games which have ARM builds available. This would incentivize developers to target the platform.
Why would Valve want to throw money at a platform that is as close to locking out third party app stores as Apple is?
Offering their client on Mac to those of their producers and consumers who are inherently motivated to use it but otherwise keeping a low profile there seems like just the right call to me.
Linux support was (is) a hedge against an OS vendor using their power to force themselves into the lucrative middle man position. MacOS support is not.
So if they have to subsidise your favourite platform, which apparently even Apple does not care about, or else they aren't "supporting" the platform, is that right?
If 70% of the sales price isn’t enough profit incentive, I kind of doubt that making that 80% would tip the scales to it being desirable to the game studio.
I suppose Proton could probably be ported to OSX with enough work. Apple isn't making it easy by refusing to natively implement Vulkan, though. DirectX to Vulkan to Metal conversion on top of x86-64 emulation is just a lot going on. It seems like no one's interested in doing the work to convert DirectX directly to Metal.