How much of the charm is just nostalgia though? I remember when Blizzard updated all vanilla character models and animations during Warlords of Draenor and it was a real sore spot for many long-term players. They were different and your character felt different even though the models and animations were of a much higher quality. The situation improved over time as they added more customisation options to the game but the community needed time to readjust. This was also helped by them adding more Allied Races and customisation options in time as well.

I'm sure Square Enix will take the time they need to appropriately update the existing models and customisation options while hopefully providing us extra features to use as well. That way people who don't like the new look will have more options to alter their appearance going forward.