I don't think it is because he couldn't generate a fair amount of wealth from his work, but rather that he chose not to, and I believe that is what lead to the success of the project.

I also don't see him as a world-renowned genius (as you put it), because he isn't one and from what I've understood from watching his talks & reading the mailing list he himself does not want to be refered to as one either. I think that people should keep that in mind when they read articles about Linus, because most articles tries to portray him as some kind of higher form of being among the likes of Steve Jobs & Gabe Newell, which I believe is not the way he'd like to be perceived when you read a sentence he spoke.