I'm struggling with the framing of all of this. I think it's clear that the author doesn't want to be involved with the realities (as unfortunate as they are) of maintaining an OSS project. There are very real issues with entitled or abusive users that have been well documented.

What I don't understand is the expectation that the money would just flow upon publishing the software with a permissive license. It sounds like a lesson learned the hard way that most people won't pay for software if they don't have to, or if they don't have a vested interest in the project succeeding. Products launched with OSS cores or with some value-added services model for revenue generally bake in some kind of monetization plan. Relying on "If I build it they'll pay me" seems a bit misguided, even if it can work under some circumstances.

The conclusion that OSS is just about people not wanting to pay any money is also problematic. The world runs on OSS, and that's arguably a good thing for a myriad of philosophical and practical reasons. The bad behavior that also happens to be an unfortunate reality doesn't negate this. The sustainability worries are real and need better solutions, but the answer isn't to abandon OSS. Even if it's the right choice for OP, his situation doesn't warrant broad conclusions, and seem less an indictment of OSS and more a misunderstanding of the playing field.