This industry makes me profoundly sad sometimes. Often.
A rich guy who wants to make more money in the tech field will be better off doing angel investing, literally getting on the other side of the counter with startup founders.
After all, capital isn't hard to come by these days. Even outside of the Valley. I have raised (and sadly, burned uselessly) money and it was no way hard. So the factor of having money doesn't mean much. Apart from that, a rich guy will have some advantages (self-confidence, ability to take risks, good initial network) and some disadvantages. Among these are poor understanding of audience for most kinds of ideas, pressure from high status relatives ('startups are hipster toys, you have to go to business school'), high opportunity costs. If we look at successful startup founders, very few come from rich families. Also, having to raise outside money provides a reality check, something which a rich kid will code using his own money has a higher chance to become just a toy - facing investors provides validation and feedback you can't ignore. Raising money is something people think is hard, and it's no way fun to do, so they avoid it whenever they can, so someone who doesn't need it will probably not do it. Which leaves him all alone with his vision...
I seem to remember that many entrepreneurs are born to upper middle class parents.
Not spoiled enough that they cannot work, but still fortunate to have a safe upbringing and be risk tolerant.
(I do agree with you that people are born with very different prospects depending (among other things) on parents social-economic status)