If Bayonetta was in, she would be rocking that short hair styleYeah, but everyone's hair is long in a reasonable way. Pally's hair almost scrapes the bottom of the floor. Peach, Lucina, and Rosalina have hair around shoulder length, ZSS's high ponytail is about shoulder length, Sheik's tail does whatever, and Zelda's hair is braided which I guess keeps it from moving around. Realistically, Pally's hair is free to roam around, but imagine programming that. It'd be hell and a waste of time when you have 50 other characters to work on. They could have somehow said she got a haircut to make it easier to animate.
heck even her classic beehive couldn't possibly be messed up.