While you're not bound to a specific charger, most modern phones(outside of Apple phones) can only reach maximum charging speeds if you (indirectly) pay money to Qualcomm. That will probably change going forward with the new rules on standardized charging.
This isn't really true anymore, USB-C PD (which is technically just USB PD but there's no standard for using it on anything but USB-C) is displacing QC for most applications. It is however something where most chargers and devices will likely try to support it for the forseeable future, though, in the name of compatibility (nowadays you can get chips from TI and the like which will basically try all the standards that they can, to find the fastest charging rate). Also, AFAIK there's no licensing fee required to be compatible with QC.
https://www.usb.org/usb-charger-pd says "The USB Power Delivery (USB PD) Specification enables the maximum functionality of USB by providing more flexible power delivery along with data over a single cable."
The interesting bits of the spec use extra pins from Type-C, so for the most part it's Type-C's charging norm.
...and even aside of USB PD, USB-C The Connector does have a standard way to signalize maximum charging current (0.5/0.9A, 1.5A or 3A at 5V) without using PD.
