This is completely false. Corporations and Venture Capitalists are the ones who capture most of the value from open source projects. Independent developers got screwed over big time. We are the biggest losers. To the point that we probably would have been better off without open source. I've met popular, very skilled open source developers who can't even make a living as developers.
The top 10 open source developers in the world only earn a high/normal salary (e.g. Evan You of VueJS earns about $200K from Patreon; probably less than what he got at Google as a regular employee). He probably also makes money from conferences and talks; it's not bad, but if you look at the top musicians in the world, the 200th most popular musician alive probably earns millions per year.
The 200th most popular open source developer alive is probably a homeless person.