I did my RHCE bootcamp back when RHEL 5 was just released and the bootcamp course materials were not yet updated for it. The instructor worked around this pretty well. One of the earlier topics was SELinux, where he stated we would cover it for the course, but it's not on the certification exam and it's not needed past that part of the course, so we would disable it once we were done with the lesson. It's been well over a decade so I don't remember if this was day 1 or 2 of a 5 day boot camp.

Disabling SELinux and implementing more manageable controls has been a default for me for quite a long time, even before my certification. My preference is for apparmor, to be honest.