mysqld_pre_systemd fails when starting MySQL on Fedora
As mentioned in the comments, the /usr/sbin/semanage file was not working properly. After using the dnf provides command (dnf provides /usr/sbin/semanage), dnf told me that this file was from the policycoreutils-python-utils-3. 1-4.fc33.noarch, so I reinstalled it with dnf reinstall (dnf reinstall policycoreutils-python-utils-3.1-4.fc33.noarch), rebooted, and my problem was solved.
However, I ran into another problem, again in the same place, which I've listed here.