Depends on what you’re looking for. On Steam you get stuff like Steam Input, and ofc having it be tied into the Steam ecosystem, which depending on how you play pc can be a big deal or not so much. Plus if you plan on playing on Deck, it’s a bit easier if you own it on Steam.
With GoG it’ll be DRM free, which for many people is a massive deal. Basically once it’s downloaded it has zero ties to GoG, meaning it’s yours and yours alone, you can do whatever you want with it, back it up, turn off your internet and play it whenever you want. You can even download it from the website without having to install the GoG client.
Plus through GoG you can easily install the Fallout London mod, which may be a nice bonus depending on you.
Ultimately I’d say GoG unless you’re heavily invested into Steam and would make use of the integration with the ecosystem.
Exactly, yeah. It’s not super important, like in FO4 idk how helpful it’d be, but it’s a game changer sometimes. I played through Kotor on the Deck by using Steam Input, and made it feel practically native with next to no effort.