The specific case I was raising was someone with 2-armor and 1-armor from Rasputin for a total of 3-armor. The question I should have put forth was "do you all let people walk around in 2-armor all the time or do you put some restrictions on it?"
Well, in that case I´d look for moments when he´s not wearing it: they attack while he´s sleeping, having sex, drinking at the club, etc.
If the character insists on using armor all the time, make a hard move or rather have NPCs react to that. A girl could mock on a PC for trying to dance in the bar while wearing full armor. Hard moves might include -1forward, acting under fire, etc.
Also, a PC failing a move against a gang might see himself overwhelmed while many hands remove his helmet. A hit on a 0harm move roll might have one piece of his armor drop, break or ruin, leaving himself exposed for easy AP harm. After the battle, repplacing that part would be easy task, not even 1 barter. But in the moment, is serious trouble.
Anyway, don´t do this all the time. After all, you´re still a fan of the characters and having their badass armors shine is part of that.
If the player answered "Oh, I can totally use force by simply walking up to someone", "Getting shot doesn't really bother me anymore" or "They're too scared of me to shoot straight" that would be no problem. My objective is to provide a consistent world, not get at the players.
Don´t overlook that you have to make AW seem real. If the player chooses to suffer little harm while seizing by force, something
has to happen in the fiction to make that possible. It could be running and dodging, it could be the PC being faster than his enemies, shooting them before they can aim, it could be what you said, all of them becoming too affraid to shoot at the moment. Whatever it is, less bullets hit the PC. but it just can´t be the character walking idly and eating up all the lead. Because then what happens is what you felt then, that AW is not that real (I´d feel that too).