The original is forever frozen in time as a memorial to Terry’s genius, but there is an (at least somewhat) actively maintained fork, which has added features of which Terry himself would not have approved - https://github.com/Zeal-Operating-System/ZealOS is the main one, which was last updated only a couple of months ago; by contrast, Minix’s last commit appears to have been in 2018 - https://github.com/Stichting-MINIX-Research-Foundation/minix

But maybe that’s the answer for MINIX too - maybe one of the people who have authored all those unreviewed PRs might start a community-based fork. If all the activity moves to the fork, there is a chance the originators might officially bless it