Too many get caught up in the "USB-C" connector, and forget about the modes and power delivery. That said, AFAICT the May 2022 revision states (pg 6):

"the devices should incorporate the USB Power Delivery (USB PD) standard (as described in the European standard EN IEC 62680-1-2:2021) and ensure that any additional charging protocols allow for full USB PD functionality (new annex Ia, part I)."

Then the referenced: "EN IEC 62680-1-2:2021" standard specifies

"To facilitate optimum charging, the specification defines two mechanisms a USB Charger can advertise for the Device to use: 1. A list of fixed voltages each with a maximum current. 2. A list of programmable voltage ranges each with a maximum current (PPS). The Device requests a voltage (in 20 mV increments) that is within the advertised range and a maximum current."

But those regs get over my head quickly, so someone else may have better luck interpreting them.