While that‘s true right now, a big patch called „Economy 2.0“ is expected to drop this week (more on that here and here).
I really hope this will be a successful first step of making the game actually better than its predecessor. Unfortunately the economy simulation is only one of many issues which make me want to play something else after a few minutes of gameplay. I think it‘ll be at least another year until they‘re able to fix all these minor annoyances, which sum up to one very big annoyance. Like not being able to place stuff sometimes without any obvious reason. Or those ugly, steep pathways on lots, when the connecting street isn‘t completely flat. Or missing animations for firemen, which currently only have to drive up to a burning building in order to stop a fire.
Cities Skylines was a better Sim City (2013) and was justifiably loved for that. For now, Cities Skylines 2 is unfortunately just a worse Cities Skylines.
I think we‘re in a very different situation right now. Proton has become so good that it‘s just not necessary for most developers to do anything to get their game running on Linux. When Macs peaked in the hardware survey, the compatibility tools were far less powerful and developers had to actually invest time and resources, if they wanted their game running on Mac.
I also think that the Steam Deck is absolutely being recognized by many developers. Even big publishers proudly announce their games being playable on it. And having games optimized for Deck often improves them on Linux in general.
So I really wouldn’t worry about developers not specifically targeting Linux. Even without that, gaming on Linux is in the best spot it has ever been and is steadily improving.