Yes, but Tiers (which is not a new concept) represents the everyday collective capabilities of a range of levels of a party.
Levels do that, too. There is no difference between having a adventure going from 5-10 or having an Expert tier adventure. The entire "Tier" terminology is unneeded and can be replaced by levels. The only thing they do is to provide marketing buzzwords (neutral) and to make the D&D progression even more rough than which is already the case with having levels in the first place (bad).