4 is really enough (fighter, two damage dealers and a healer), 6 is already a clutter, means that developers need to have 50% more enemies in every battle making battles longer and screen more cluttered.
Maybe 5 would be a compromise, but 6 party members is an outdated game mechanic already.
6 party members outdated?? in what way?? Like saying having more than 5 classes is outdated...day/night cycles outdated....using the mouse is outdated...