I mean, I guess that's true isn't it?
I feel like the odds of getting a good story in a novel are higher, but the complicating factor is that most RPGs are essentially story + game kind of superglued together, and thus you can end up with quite disparate levels of quality, so you're more likely to end up with a good game with a weak story or occasionally vice-versa. Complicating the issue is stuff like BG3 where the overarching story is maybe only okay, but the wonderful characters (not just the companions, loads of NPCs and villains and so on) more than make up for it.
Whereas with a novel all you have is the story (including characters etc.) so you just avoid novels with bad stories mostly, which means it's less likely you bump into a bad story there.