I don't think PG is arguing that Gates is rich because of IBM's failure. I think he is arguing that Gates is fantastically rich because of IBM's failure. PG states in the essay that someone like Gates who is smart and hard working will be successful. ...but being successful and being a multi-billionaire are two different things. Being a multi-billionaire requires luck.
And, yeah, it’s pretty clear that IBM dropped the ball on this one. There was a good 10 - 15 year period where IBM could have easilly crushed (or bought) Microsoft.
"Battles are decided, Sethra told me, when timing and momentum and courage all come together and, at just the right moment, someone fails to make a critical mistake and doesn't manage to miss a vital opportunity."
And, yeah, it’s pretty clear that IBM dropped the ball on this one. There was a good 10 - 15 year period where IBM could have easilly crushed (or bought) Microsoft.