Yep, I can vouch for this. I work on the Redux JS libraries, entirely volunteer. I spend a _lot_ of time maintaining them, but I'm mostly able to do that because I can _choose_ to do that work when I feel like it, with no outside pressure. Adding financial obligations would likely cause a lot of additional mental overhead I don't want to deal with.

Besides, in my case at least, I spend so much time working on Redux stuff as it is that money really couldn't even make me do more than I already do anyway :) The only thing I can think of that would qualify would be getting paid a full salary to do maintenance full-time, and I don't want that either. I like building other stuff for the day job, and Redux stuff in my free time.