It's all a bit moot. Gaming is an ecosystem, and MacOS is not a big part of it. Even if Apple supported all the things it needed to, developers still wouldn't build for it, it's too small a segment.

Apple also has no buy in for the segment of gaming people wish it supported. Where SteamOS and Windows both have first party AAA game development studios.

It's not moot; it's software! So many developers put their pearls before swine these days, when the technical side of things couldn't be more clear.

Apple wants the same level of control Microsoft had with DirectX. It is blatant, and they're fighting for it even harder than Microsoft did. There's nothing wrong with offering a high-level API, but there is a problem with avoiding industry standards for the sake of maximizing your market size.

Stuff like the Game Porting Toolkit demonstrates just how deeply behind Apple is. They're desperate to prove how capable Metal can be, without acknowledging why nobody targets it. It's not surprising that a DXVK port could also support Metal. It's just not what developers intend to support; not upstream, downstream or direct from Apple. That sort of pointless insistence is where I draw the line between "just business" and "being an anti-competitive asshole".