With Linux gaming clearly showing it’s becoming more popular, and with GOG under new ownership, there’s hope yet that GOG will improve their Linux support.
GOG does currently support Linux — well, kind of. They publish Native Linux packages for various games, which depends on the developer (just like Steam does without Proton) but they have a very limited support of distributions, which can cause problems installing Linux games from GOG due to dependency mess. That, and GOG Galaxy does not support Linux.
There’s easier ways to install games from GOG on Linux / SteamOS though, which you can check out in our GamingOnLinux Guide. You can even do it directly in Steam if you want to.
The more the merrier. Heroics launcher allows GOG to function but it currently feels pretty janky compared to Steam. I might actually use GOG if they create a better UI/UX than they currently have.