I wonder how many guys who have have written or significantly maintained "household name" level FOSS products just earn a corporate sinecure somewhere as hypercompetent remote sysadmins or ICs or something. Folks who don't necessarily care to earn top dollar, with all the headaches that entails, but also almost never have to actually work more than 2 hours in a given day to keep the ship going, and the arrangement is just so cozy and gives them enough time to themselves to work on their actual passion that they accept the arrangement.

I know of at least one recruiter who does something like this and specializes in greybeard hiring, and it seems like a steady niche if you have the network to pull it off.