As stupid as this will sound, turn off Galaxy, turn it on again. It will unfuck itself, finish the patch appliance, download a 200+ mb patch, unfuck itself again and launch.
P.S.: I know y'all feel like this is not snappy enough. But give CDPR some leeway. They have to unfuck a bunch a crap for both Steam, GOG, consoles and wherever the fuck else they got CP2077. It sucks. I know. But we've waited for 3 delays. We can bother to wait a couple more hours for the installer to unfuck itself. Bear with it. Please.
It did not 'unfuck' itself. And I'd give them slack if they didn't repeatedly delay a game. They've had literal years to prepare the launch. This is silly.