...so what's my point here?
For foundational libs (including xz/liblzma) tons of people depend on, it sure would be nice if, assuming there are people who _want_ to be full-time maintainers, get to actually be paid for doing so.
For something like the stb libs? I really don't know. I don't think we're foundational. If those libs disappeared overnight, nothing terrible would happen, people would just use other alternatives.
And "any open-source lib anywhere in the wild must be up to professional quality standards and respond to all bug reports in a timely fashion" is also a bullshit standard to apply to anything. It just doesn't work that way.