belts and wraps are safety equipment for powerlifters who are strong enough to lift weights that the body's structure cannot support.
The briefs hold the hips together, belts help support the lumbar spine, wraps help keep the knees from collapsing.
Then it was discovered as technology developed that they could use the safety equipment to go even heavier by using different materials, making it tighter, etc... Then it evolved from safety equipment to lifting equipment.
Hey, if that's your goal - then use them. Just to make a better body, they don't really have much of a place other than for safety.
Myself - I was told 8 years ago that I was heading for a wheelchair. 3 years ago I was there. I started training to rehab myself, trained completely raw and I'm now in the best shape of my life, working, and supporting my family like I should be doing.
There are still bad days, I'm more prone to injury due to my condition, but I don't let it stop me. I've found that if I'm having a bad day where my legs aren't working right a back belt is a good thing to help me keep my form. I just put it on snug, not super tight then use my own "natural lifting belt" to push my abdomen and back muscles out to make it really tight. When I do this, I don't get hurt. If I suddenly become fatigued (my problem is CNS and not muscle) and can't finish my squats - I'll wrap my knees in addition to the belt to make it through.
So yes, they do have a time and a place. But should not be a part of every workout, every rep, every time.
If you are afraid of injury but are having a heavy day - say for example your last workout of 5's and don't quite feel up to it - they just might save you from a debilitating injury.
I'm really new at HST and don't completely understand it all yet, but to me it seems that those maximum effort days are few and far between - like about 2 weeks apart so even using a belt for those days use would be pretty minimal.
I was once a "Raw Nazi" as my powerlifting friends called me. I've learned better since then after a few injuries. However, I'm thankful for my last injury - it did lead me to HST while looking for a lightweight plan I could still grow with...and GVT didn't appeal to me at all. The last 7 weeks of progress have been the best of my life.