The Bastard Executioner

I have two main problems with this show. First problem is that the chainmails are not riveted (and all chainmails used to be riveted). My second issue is that I honestly do not understand why they bother to wear them, because these chainmails are apparently from butter and every single cut goes through. In reality chainmail was a very good protection and wearer could be killed only by strong crossbow, very heavy long bow, cutting to uncovered part, or bludgeoning, usually with hammers or morning stars.