Hello,
I would like to preorder the physical Stalker 2 ultimate edition and learned that there will be no cd included, but a steam key. As I would prefer to have this game on GOG, I wondered if there is also the option to get a GOG key instead?

Very common theme with physical editions of PC games. Back in late 2000s early to mid 2010s when they were still releasing clamshell cases that were part-cd/part Steam... I get it... but at this point the only people who want physical copies of a PC game are the same people who are going to want DRM free so I have no idea why they go the Steam key route.