Unfortunately, the three people who programmed the vast majority of modern SuperTuxKart and managed the community were bullied out of the project a couple years ago. [1]
The new team lead was somebody who seemed to have a habit of stonewalling [2] ideas and code contributions from both community members and the dev team, talking down about "newbie-tier players" with "zero skill", and [3] hyperfixating on "balance" (in what is fundamentally a kids' game) without room for fun or discussion. The lead artist, who made basically all the tracks that are worth looking at, and whom I'd worked with now and then to get a couple contributions included, eventually disappeared too.
Naturally, commits, contributors, and blog posts/updates are now at an all-time low. [4]
So, don't let your group dynamic be taken over by domineering personalities, I guess, is the lesson.
1: https://blog.supertuxkart.net/2019/05/my-departure-from-supe...
2: https://forum.freegamedev.net/viewtopic.php?f=17&t=8086&p=77...
3: https://github.com/supertuxkart/stk-code/issues/3888#issueco...
4: https://openhub.net/p/supertuxkart