Open Source is not broken imho.
The challenge for single-maintainer projects is that they come to identify themselves with their project and that can create a toxic environment.
Its the same with other hobbies. If you are so into fishing/cycling/etc that you start to spend less and less time on your job/family/etc then things are also bound to blow up.
If you start a hobby you need to be able to draw a line on how much effort you put into it. And yes it will be tough to reduce/stop spending time on it. This is your masterpiece, your baby so to speak. But if you don't you have to accept the consequences.
Having said that, I feel sorry for the guy. But even if he would stop tomorrow the world will continue and solutions will be found.