There are already some huge maps out there, Just Cause 2 and 3 both have maps at around 1000km2, and those games are beloved by their players. But if the next Cyberpunk game was announced with Night City now being the size of an actual large metropolis, say like New York, would you say that’s too big? What determines what “too big” is?
I would argue that Fallout 3’s map is ridiculously tiny.
It has been a little while since I last played it, but I found that scale-wise, it felt small (I’m guessing this is what you mean) with major locations too close together, but content-wise, it felt sparse, empty and ultimately pretty boring, which was the much bigger issue in my enjoyment.