Sure... Which is why Valve has built Proton, which makes nearly all PC games run on Linux... Sure, the developers of the games themselves should have made the Linux port, but for many developers it's cost prohibitive to support another platform with very few potential customers.
But the more players who run Linux (and Steam Deck by extension), the larger the incentive for developers to support Linux natively. And in turn more games will get made for Linux, which will draw in more people to switch to Linux.
So as long as my game runs, then I don't care whether it was the original developer, Valve or an open-source developer why wrote the code that made it work. And luckily I'm one of those people that don't mind having to tinker a bit to make things work (hence why I'm on Linux in the first place)
If we as gamers stubbornly refuse to switch to Linux until our games are natively ported, then developers might as well just develop their games for Windows, where the players are...