He introduced millions of hackers to their first computer. I'd call that a contribution, indirect as it is.
Computers for everyone? Yeah, it's the result of marketing, in a lot of ways. But it's also the result of an intuitive understanding of users--of users, not borderline-Asperger's hacker types--and the business discipline and leadership to say "we're going here, I know it's not easy, make it happen." Vision is valuable. Technical contributions are so much less valuable without the vision to apply them to do something great.