Columbus was wrong. While the grandparent posits a hypothetical where there was no land in between, that's not what Columbus critics suggested -- they suggested that the known size of the Earth was such that a more economical route to the Indies from Europe sailing West was not a reasonable thing to expect.
They were correct, and Columbus -- who insisted that he had reached the (East, now, because of the confusion he caused) Indies -- was wrong.
It was still a gamble where the outcome was entirely unexpected. They were both wrong about their expectations: finding the indes, or finding nothing and running out of resources.
True, but one could say that the critics of Columbus based their opinion on reason and knowledge: world is too big to find India that way, and you can't know that there's land in between.
They were correct, and Columbus -- who insisted that he had reached the (East, now, because of the confusion he caused) Indies -- was wrong.