Nobel Prize is just some dude who wanted to do something nice with money he made selling dynamite. There's no reason to imbue it with responsibility for picking which authors deserve to be immortalized.
Sure, it may be too much to say it's someone's "fault". My point is just that even the people who give Nobel prizes probably agree that the aforementioned authors deserve getting something at least very similar to it, they just didn't get it because of some fake scarcity that implies someone else deserved it "more". So although no one has any obligation to change the tradition, it might be a good idea to do so.