Well training and ideas are different in parts of the world. So opinions differ, that’s ok. We have far fewer ex-military personal and far less firearm incidents, so I think that is a reason why we have less emphasis on trauma kits and more focus on everyday injuries.

An example what we are taught and why:
We are taught that overpressure with ace bandage can cause nerve damage and damage to valve in your blood system when applied incorrectly. So there are even different method for professionals (should have enough experience applying correct amount of pressure) and amateurs.

Professionals: Apply Ace bandage directly

Amateurs: Apply roll of synthetic cotton wool first, then apply ace bandage. (to prevent over tightening; the cotton wool spreads the force and makes is more idiot proof)

Edit/note: I only speak of applying ace bandage as i'm trained to, not where it's for. I have first aid training and i'm a trainer, but not a medical/first aid trainer, so I'll not go in to where this actually applies and when you use it,