I believe that it is a replica, for lack of a better word, for lore purposes anyway, but for game play purposes then it is Dwemer armor, the thing your forgetting, not everyone who plays elderscrolls knows the lore and is interested in it, maybe they are playing to get fun out of it or they just like killing things, I don't know but all i'm saying is, you need to look at this in a more gameplay aspect rather than a lore aspect. On the other hand, you do raise a good point.
I see your meaning, but if that's the case then wouldn't the Dwarven Armor in Nchuad-Zel be different in appearance to other the armor made my modern smiths?
I know from a gameplay perspective it wouldn't make much sense to people that aren't lore nerds, but suppose everything in the lore was applied in-game. If so, then the only explanation for them looking alike that I can think of is that the armor in the Dwemer Ruins is used as a basic blueprint to make Dwarven Armor.