>>100739694in-universe, it's been obvious that tony has been sacrificing tankiness and DEF for more mobility and jack of all trades. iron man 3 shows he built suits for every situation like in the comics, but the ending reinforces that he is iron man, not the suit.
he makes it faster and quicker to respond but it can't take bigger beatings. the nanosuit is the pinnacle of this design philosophy. previous armors would just take the hits. but now he's mobile enough to dodge most attacks and if he needs to take the hit, he just moves the nanomachines to form a shield in the direction of the attack, while still maintaining other options, such as escaping/counter-attacking faster
i really did like how in infinity war, they weren't infinite nanomachines, and thanos kept taking chunks of them off and stark had to start retasking different parts of his limbs/became more exposed to get the suit to do what he wanted
