8 vs 12 is big difference in game mechanics. given the rate of speed in which certain species of mobs move, at 75 is was the difference between able to solo and dying. rdm or blm for example and even smn. losing aggro from distance and dot/nuke soloing is something they are being mindful. especially for a job like sch.
now of course, the game has changed much since then. s.e has already mentioned possible changes to hnms like Tiamat, so we will have to see. if any changes happen i think, it will be on the availability of items like gaiters, vs giving emp 12% movement speed to jobs like smn blm sch and whm.
if anything needs changes in the movement speed department its not being able to flee from raptors.