Earlier quoted context omitted.
They also dropped the Mac version. They complain there are few Mac players on Steam. Well, I'm not going to buy it if it doesn't run on the desktop OS [1] i use most, duh. [1] My Linux boxes are headless. And the windows boxes I have to RDP into them. That may work for a game with a beginning and and end via Steam streaming or something, but not for a forever game you just keep around.
While individual game developers choose whether to support macOS, the broader phenomenon of developers dropping macOS support is Apple's fault. They either have no interest in being a serious gaming platform, or else they've made catastrophic missteps in their quest to stay relevant for gamers.
Apple insist on having their own apis and they don’t maintain compatibility for older software for very long, these 2 facts explain things fine on their own. Game devs don’t want a major support burden, they’re happy to patch here and there but constant dropping of apis or even architectures is a lot to handle. The bigger impact is that macOS ends up with a lot less old games that still run, if you need a critical mass of games to become a gaming platform, that constant bleed of legacy games will always slow macOS down.
As for gaming specific features, Metal is a perfectly fine api whose only real problem is that it’s different from the other platforms. Maybe not the best, but certainly not terrible. They also have a really nice capability floor, it’s practical to make a modern game work on any Mac from the last X years (maybe the neo complicates that a bit).
There’s probably a few gaming specific capabilities they could improve on, mouse input especially, but that’s never been the real issue.