Not, it is not true, they won't will weaker, they will still same.
Only others chars will stronger.
Some OP skills, almost every passive armor skill (or every1) will give more p.def (right now only around +100, later will around +1000)
And archers get only bonus to magician skills to 10%m.def or 10% less mag. dmg , still same 10% less from mags.