It's through Proton, but the game runs flawlessly. Do note that you're really going to want a controller for this one. Playing this with a keyboard is a miserable experience. Another thing is that there's an unofficial tool for importing images over your custom graffiti, but it's for Windows and I've never tried it with Wine.
If you haven't already checked it out, Armed and Dangerous is by the same studio and is very similar in terms of gameplay and humor. Not quite as polished, but a lot funnier in my opinion.
I did play it. It was silly and fun, but the gameplay felt so much more banal than GCK, which was amazingly All The Genres and shockingly successful at it.
Yeah, I thought that was so cool when I played it the first time. Gives you some insight into how the neutral parties went about trying to live their lives.
Although I really liked the story in TIE Fighter too with slowly beating back the rebellion while also trying to prevent internal sabotage and spies from stealing the TIE Defender.
Hands down. One of my favorite games of all time, an open world, hilarious, fun, sprawling adventure with music that slaps SO hard. Originally titled Star Control 2, went through some crazy copyright hell but now is getting an official sequel soon, over 30 years later.
EDIT: Oh wait, you said Linux. I think it works on Steam Deck and Proton though, does that count?