What does this have to do with engines? AFAIK, Valve developed their own engine "Source 2". At the end the article contains
> Regardless of numbers, one of the reasons Valve is reluctant to develop CS2 for Mac is that Apple devices do not provide native support for the Vulkan API that the game is based on. Vulkan was designed to succeed OpenGL and address some of the latter's shortcomings, and while there is an open-source library called MoltenVK that provides a Vulkan implementation on top of Apple's Metal graphics API, it still lacks some of Vulkan's advanced features.
Valve isn't saying there is some technical problem with Metal that prevents game engines from using it, so how are other game engines supporting it relevant? Valve isn't supporting it because too few of their customers use Macs for it to be worth it to Valve. It may be worth it to other engine developers, or maybe those other engine developers are wasting their time/money, but in either case that has nothing to do with it not being worthwhile for Valve.
Valve publishes the relevant statistic btw. They have less Mac customers than Linux. Mac users are fringe and just aren't very relevant to Valve.
>...while there is an open-source library called MoltenVK that provides a Vulkan implementation on top of Apple's Metal graphics API, it still lacks some of Vulkan's advanced features.
The existence of other games/companies that do choose to support MacOS is irrelevant. Valve isn't those other companies, they're making their decision based on the statistics of their players, not because they think it's technically impossible for games to support Macs.
To be honest it seems like you're a bit offended that Valve is dropping a platform that isn't used by ~99% of Valve's x, so you're saying essentially the same thing but with a sour grapes twist. That's why you brought up iOS market share another comment with a smug sort of "gotcha" tone, despite iOS obviously not being relevant to Valve at all.
Listen, nobody is denying that MacOS and iOS are relevant platforms generally, but they aren't relevant to Valve and this discussion is about Valve. There's no reason for you to be upset about this.
> Regardless of numbers, one of the reasons Valve is reluctant to develop CS2 for Mac is that Apple devices do not provide native support for the Vulkan API that the game is based on. Vulkan was designed to succeed OpenGL and address some of the latter's shortcomings, and while there is an open-source library called MoltenVK that provides a Vulkan implementation on top of Apple's Metal graphics API, it still lacks some of Vulkan's advanced features.