the knee wraps my just be put on snug not super tight. at his age and years of pro wrestling as well as football, a snug knee wraps will help the knees feel good during squats of such volume.
the belt is also a good idea. remember, the rock had a serious back injury during his college playing days at the U. when squatting high reps it is easy have a fail in ones technique. the belt is a good idea to help protect his back from injury.