The calculus is very very very boring and simple. Game devs will support every single platform on the planet in which the cost to support that platform - both directly and long-term maintenance - is less than the increased revenue that platform provides.
It is not uncommon for indie games on custom engines to support Windows, Playstation, Switch, Switch 2, Xbox. And, depending on the game, iOS or Android. Sometimes macOS although that's increasingly rare.
Native Linux builds are pretty rare. Especially before Proton got pretty good with Steamdeck release.
Supporting Linux is a monumentally tremendous pain in the ass. Radically more than literally any other platform. It is hands-down the hardest and most painful to support natively. So painful that emulating Win32 is a clear win. Valve's runtime helps a lot. And supporting another path is just a waste of time.
Very sad!