Does fast charging damage your phone's battery?
Every lithium-ion battery wears out. Phone makers build fast charging around that fact, and what they warn owners about is heat and long hours at full charge.
Phones
How phones charge, what wears their batteries out, and what their makers advise.
How USB-C Power Delivery works: the short conversation before your phone charges
A USB-C PD charger does not simply push power at your phone. It lists what it can supply, the phone asks for what it wants, and only then does the voltage change.