To be fair, part of that comes from her old ult was much harder to use effectively without voice coms. Since it only provided movement speed, CDR (Which only makes a difference if you get the stat BEFORE you use your skills), the mana reduction (But then who doesn't pick up some form of mana sustain anyway...) and the heal proc.
It was very potent in competitive games, that had coms so you could pop the ult before a teamfight and everyone would benefit from the CDR and the speed to engage/disengage. But in Pub games it was really difficult to get good value from.
The new ult is much more straightforward, it being a much more self contained damage up/down with heal and damage procs. You don't have to worry about what skills your allies have used, what's happening on the map. You just press 4 during a teamfight and it has its impact.
The issue is how to make it work. Without it becoming OP in deathball situations late game (When it's already at its strongest due to all 3 laurels completed). While also making it distinct so you don't just feel like Amaterasu (Who's primary feature is the potency of her power and speed auras)What if Nike's Passive was AoE then make a few adjustments as needed?
Since, yes, in theory, removing the global aspect of Nike's passive will open up room to reallocate some power to her skills so they feel better. The issue is well... Keeping the passive feeling unique and also useful. It probably doesn't help that it gives the 2 best stats in the game, power and movement speed, which will always be pretty strong when you're granting it in an AoE (Because making your carries just BETTER than the opponents for 0 investment is always good)