Windows dominated desktop development for years, and Macs did the same in the creative world. So a lot of developers naturally know those systems best. Linux has always had the problem of fragmentation, different distros and different library versions all pulling in slightly different directions, which makes it harder to target reliably. That’s why things like the Steam Deck or Ubuntu LTS matter so much, because they give developers a stable baseline instead of chasing down tickets caused by someone building with the wrong version.
Tools like containers and Flatpak have improved the situation, but the underlying complexity is still there. When a studio doesn’t have the time, budget or experience to handle that, the Linux port is usually where the cracks show. The ones that tend to get it right are teams with stronger engineering depth, which is why you often see the better native ports coming from studios behind RPGs and sims where crossplatform work is already part of their pipeline.