Some cloaks are gender restricted and only the race of men (Kingdom of Altar's race) can use the boots.

I'm guessing the armor that dropped was from a level 3 quest that involves killing a bunch of spiders.  If that's the case it is also restricted to males from the race of Men.  Or it can be sold for just over 1,000 gold.  It's basically legendary plate armor (both have 12 armor) but it lets you equip gloves with it.

The logical answer is that they were meant for Campaign only, and not for sandbox.