Currently on Fedora the Security Enhanced Linux (SELinux) functionality that’s there by default can be disabled at run-time via the /etc/selinux/config but moving forward with Fedora 34 they are looking at removing that support and focusing just on disabling via selinux=0 at the kernel boot time in order to provide greater security…

Source: Phoronix – Fedora 34 Aims To Further Enhance Security But Will Lose Runtime Disabling Of SELinux