I don't think this is entirely accurate. There are a lot of companies out there that end up being bought by wealthy investors or companies. These investors or companies may have gotten their riches through inheritance or by some other means.

Even then, The Man may have been a startup, but money and power can transform people in surprising ways, or they might have been The Man from the beginning.

I think that generally you don't really want to be working for the man whether it's in the context of a startup or a large company.