AppArmor is used by debian/ubuntu, while selinux is used by Redhat and Android. Don't think any of them is more dead than the other. The refpol used by redhat isn't very restrictive/complete and no one except for big corps are using it. Apparmor is barely looked at too in my experience.

In fact AppArmor was only "recently" enabled by default in Debian starting with Debian Buster: https://www.debian.org/releases/stable/amd64/release-notes/c...

apparmor is also the default linux security module for suse