Closed source sells because open source devs don't know sales or marketing. In many cases, developers are the only users that the devs even acknowledge.

Just look at the successful/popular open source projects. There are nearly no paid open source apps, though most of everything is turning into software as a service.

Open source is built in such a way as to make outside investment very difficult to justify by most private investors. Why pay good money for something you already get for free? This is a flawed metaphor, because investors aren't purchasing anything, as investment isn't a transaction, but I think that's why we don't see more sales and investment in open source. It seems fundamentally ill-suited toward those aims and ends.

I think successful open source businesses are outliers, and as such are pretty interesting. The only recently founded one I can think of that does hardware is Flipper Zero. I'm sure there are others.

I'd be curious about who others think are the outliers in this reading, as those are folks whose work I'd love to hear about.