The onus is on the maintainer(s) to work on the project as much as they can and want to, if people are creeps who try to socially manipulate maintainers to do free work, I think we need mechanisms to help mitigate that. For example, I think maintainers should be encouraged to delete GH comments they find offensive or harassing. It's their domain, they should keep it in a way they find enjoyable.
But turning open source into a job? No thank you! Adding money to something, overwhelmingly almost always in my experience, makes it that much worse and stressful. Money is not the answer!