3.5 mm headphone jacks are trash, its the component that fails every time on a portable device, giving you static unless you spin the headphone cord within the jack to the right point. a lightning port headphone jack will likely eliminate that completely.
I never had a problem with 3.5 mm headphone jacks. It's the 3.5mm headphones cords that seem to always breakdown, especially on cheap headphones.
But the lighting cord will have the same issue. Lighting cords from Apple eventually go bad when moving it around too much to the point I can't charge my iPad anymore. If I get a cheap non-Apple lighting cord from a store, it works for a couple weeks, then eventually slow charging and the popups of not compatible are the problem.
I don't think a lighting port will solve anything issues people already might experience with 3.5mm jacks.