One thing is making fighting hard, another is making it pointless.
It's not entirely an armor issue. I'm sure you know that even dorfs die quite easily from blows to the head. Sure, they can wear helmets to compensate but it isn't much help.
I do agree though, about the artificial 'you can't wear this' aspect. Even with modern materials, we couldn't improve much upon medieval armoring tech to protect against melee attacks. Their lives depended on their armor and it was developed in an 'evolutionary' fashion. !FUN! is one thing, being faced with attacks you can't hope to defend against is just frustrating.
I have kinda felt the same way about ALL combat in DF, to the point of ragequit and not playing for a couple years at least once. The 'game' should not be in trying to master the GUI and its quirks. The 'game' should be the game; the interface as effortless as breathing - or as nearly as possible.