Debian has an elected leader that is not paid and has pretty limited authority overall.
There's also the Linux kernel, with Linus doing both managerial and technical work, running circles around Mozilla's leadership in both. He makes just a few millions per year, less than Baker did even two years ago AFAIK.
FreeBSD seems to have three paid directors: https://freebsdfoundation.org/about-us/our-team/
Debian has a leader and also seems to be more a volunteer organisation than a full company: https://www.debian.org/intro/organization
Thoughts from Derek Lowe (In The Pipeline).