[shawabawa3]

There are so many more factors than heat though

For one, I thought charging slower was better, so could the increased heat be offset by that? Also, it's more heat per joule transferred, but over a longer period of time, is that not better than sudden heat from fast charging?

[stevenhuang]

Heat is the primary factor, and even with fast charging the inefficiencies of wireless charging will mean the latter will dump more heat into your phone.

The constant current phase of fast charging does not generate much heat in comparison at given wattage as it's able to charge up your phone much more quickly at higher efficiency until it switches to trickle charging at ~80%.