I have observed this as well. It appears to be a bug with Conan Revision (#246072/26452).
The bug is as follows: the Temperature UI for ALL armors appears to show 1 bar of heat and one bar of cold insulation, instead of the values they should show.
Stat window is also useless. If you wear 5 pieces of pretty much anything, it just list 5 bars of heat and 5 bars of cold resistance. The indicator itself is incapable of showing more, so you can’t tell if you have more or not.
Also, the issue isn’t with just flawless and epic armor - as far as I can tell, every single armor item lists one bar of heat and one bar of cold resistance, and 5/5 in the stats when worn.