Although macOS holds a high market share, it holds a smaller percentage of Steam users than Linux right now. Essentially, there's more people on Linux known to buy games than on Mac (at least on Steam).

I guess this isn't the end of the world for Nvidia users, because FSR 2.2 is pretty good, and this game will be unlikely to have ray tracing that requires a lot of upscaling anyways, but it still sucks that the only way games will run well on any PC hardware nowadays is if the developers are paid to optimize for it.