In a way OSS seems like the sort of thing that would have worked great in some hypothetical enlightened communist system that didn't suppress liberty.
Actually you got it wrong, it was precisely because AT&T could not legally charge the prices other vendors were selling their OSes, that UNIX got adopted by universities and small business, thus spreading its use in the industry.
The ones charging lots of money for UNIX clones were Sun, HP, Digital, HP, ...
I do remember, um, liberating an overlooked copy of system V/386 on 5.25" floppies that I found in a storage cupboard when I worked at PC Magazine in 1992 :-)
"A Narrative History of BSD by Dr. Kirk McKusick"
https://www.youtube.com/watch?v=ds77e3aO9nA
"Unix came into many CS departments largely because it was the only powerful interactive system that could run on the sort of hardware (PDP-11s) that universities could afford in the mid '70s. In addition, Unix itself was also very inexpensive. Since source code was provided, it was a system that could be shaped to the requirements of a particular installation."
Or as a famous talk once said: fuck you, pay me.
An extra $30k/year is pretty nice for a sidehustle I think. Mostly on track to do double that this year.
And of course, if a company asks for consulting, I charge. But I'm not focusing on consulting these days.
However a company is paying me to develop tech material for them as a content marketing strategy. At $600/article it's not a bad gig and I'm probably undercharging.
So .. uh .. the answer to your question is Yes, sortof.
You can read more about it here: https://swizec.com/blog/learned-6x-income-4-years/swizec/734...
The problem we have is that OSS creators don't realize, and often willfully ignore, the fact that nothing about opensource says you can't charge for delivering value to people. Sure, their ability to copy it themselves and do stuff might reduce your leverage, but I can almost promise you that a company which generates $10,000,000/year of revenue and relies on your software, will throw money at you if you ask. Especially if you say something like "You know, since you're not paying me for this, I can totally stop maintaining it at any point and then you'll be fucked because your business relies on this".
But many engineers don't like to be business people. So here we all are.
It's really not that hard: Do people's livelihoods and businesses rely on your work? Are you improving people's lives? Charge.
Doing it for fun and no interest in making a business? That's fine, but don't expect to make a living off of a thing you're not charging money for.