If the squatter mage has been there long enough to count it as a chantry, then there's wards and no paradox, so the melee assailant is cooked.

It actually doesn't matter as far as the combat triangle is concerned because melee armor has debuffs for magic defense and magic armor has buffs for melee defense IIRC

Also mages can freeze you and shit

Here me out, longbow is still melee range.