A lot of confusion here

Quick charge is an hardware implementation, not software, so it's not about iOS ...
Btw using an iPad 12W charger on the iPhone is faster than the standard charger, but still doesn't qualify as Quick Charge (that let you charge your phone from 0 to 85% in less than 30 minutes).
Said that, I'm happy Apple doesn't support that technology : fast charging a battery does no good to the battery itself. Considering the sealed battery of modern smartphones, I think fast charging is more of a marketing gimmick than an useful feature