A lot of hate in the comments, I think it's great that companies are in a position where they think it makes sense financially to support Linux as a target platform.
They're just trying to ride the wave of Valve's deck (and they will fail). The fact is that, since I bought the Steam Deck, I bought less from GOG and more from Valve.
And this won't change a thing: it doesn't matter if they make a Linux-native frontend to the horrible GOG Galaxy. I just want my games to launch as seamlessly as they do from Valve's UI, not yet another launcher that I have to launch on top of Valve's system UI. I am already doing that with Heroic Games Launcher, which is far better than whatever they will concoct in-house and supports many other stores.
I think this is a good lesson in why companies don't try to bring stuff to Linux: the market is incredibly resentful of products.