What would an ice attack do to Sakazuki?
It could impale him, give him frostbite that he can't heal from. I think Sakazuki bares some scars now iirc Kuzan's fruit is a cold fruit, not an ice.
Oda said their fight was a very close 10 day duel, not a fight where one of the fighters struggled with a crippling matchup advantage
Plus Sakazuki had the better Marineford portrayal and feats