To be fair, the developer was completely in control of their own exposure and workload. They just might have limited the project's popularity. And I think this

To be fair, the developer was completely in control of their own exposure and workload. They just might have limited the project's popularity. And I think this was the solution: hand off (or freeze for adoption, if you're not this big) when you're feeling done with it. It's a shame he had to get to a point where he obviously needed help before coming to that realization. I do think there's work to do around both mentally prepping someone for being a maintainer and setting expectations around what one can count on for free, but I don't see this as being peculiar to open source. Ongoing support for independent apps and components can also outweigh the profit, without the ethical freedom to just walk away from a customer if you don't feel like helping them. And don't get me started about working in a typical day job. Everyone wants as much as you're willing to give them, and metering that is a key skill.