Not many hobby projects of any kind for that matter. IMO he gets this kind of support not just because of the value added by SerenityOS itself, but because of the value he adds by making YouTube streams and other content. People feel like they can learn a lot about programming from him.

It doesn't. He says it brings in $2000/month and that this is not enough to sustain his family, but he hopes to increase it.

It's nice that he's able to indulge in this kind of hobby programming, but he must have an incredibly generous and understanding family. Clearly he can hold down programming jobs at major tech firms and could therefore give his family a much higher quality of life than $2k/month will bring, but chooses not to. Well, OK. I'd like to write an OS too, but my family has slightly higher expectations ...