There are 5%-ish code are contributed by other people, I feel really bad for not sharing the money with them. Anyway, I wish that GitHub offers the option to sponsor a project, not one single maintainer.
I put sponsor information on my open source project, and it has been giving me $600/mo in the past few months. There are only a few thousand stars on GitHub, but it's already the most popular tool in a paticular niche area.