Willing to bet its a technical thing (As everything seems to be one).
It's pretty ridiculous wanting to protect role image when you have all the casual glamours, animal costumes and such usable by all jobs which remove any identity at all.

If they really wanted to go down some sort of filtering they could easily have done
Tank, Physical, Magic, DoH/DoL

Tank
Melee + Phys
Healer + Caster
DoH + DoL