I just sit there and wonder; my last MacBook could do this, why does this $4000 racecar of a computer fail at the most basic of entertainment tasks? It feels like such a waste to have the equivalent of 3080 and yet I can't play Elden Ring, most online games or any VR.
You can't play Elden Ring or those other things because their developers decided not to put them on the Mac, not because Apple blocked them.
Apple has voiced refusal in ever adding support for Vulkan - which would immediately open MacOS to Proton and every game on the Steam Deck. It's hard to know why they hold this stance; perhaps they want to try for vendor lock in with the Metal API in the same way Microsoft did with DirectX, after all, who would use Metal if Vulkan was supported?
It's not hard to understand why Apple doesn't want to support Vulkan, you just have to know that there's some history. The first domino was that Khronos Group (GL's industry consortium, which at the time included Apple) repeatedly failed to ratify efforts to modernize OpenGL, mostly due to political maneuvering by a certain major player (not Apple) which didn't want it to happen. At some point, after years of frustration, Apple decided they were done with Khronos, OpenGL, and even OpenCL (their own baby - they created CL and donated it to Khronos). That's when they started work on Metal. Khronos eventually got its act together and came up with GLnext aka Vulkan, but this came far too late to get Apple to come back.
The idea that Apple adding Vulkan would "immediately open MacOS to Proton and every game on the Steam Deck" must be some kind of web forum mythology you're repeating, because this isn't the first time I've seen it, and in nearly the same words. The reality is that Proton is its own complex software project. If Valve wanted to port Proton to Mac, they'd have a lot of work to do even if Apple provided Vulkan. And not having Vulkan isn't fatal, either - they could translate DX3D to Metal API calls instead, or insert MoltenVK as an additional shim.
But the real sticking point is that Valve would have to
actually want to port Proton to Mac. That's the barrier, not Apple. Valve's approach to Mac hasn't visibly changed since Apple Silicon - the Mac platform is still an afterthought to them. So it's probably not going to happen.
The other thing I want to mention here is that creating their own API is expected for any company as large as Microsoft or Apple. Why isn't absolutely everything in their respective operating systems an open standard? A cynical answer is: because that would make them less money. A less cynical answer is: no company wants to deal with a bunch of external people not in their own management structure - including people employed by competitors! - making product decisions for them. Any company large enough to do its own thing (and to make it stick) is likely to try. Neither is the full truth, IMO, but they're both part of the truth.
