> DP has a HDMI compatibility mode that allows a DP output to output a HDMI signal, but at the wrong voltage. The external adapters are just level shifters to bring the signal voltages into compliance with HDMI, but their entirety passive devices.

That's DP++, which is not supported on all DP outputs, and notably is not supported by the USB-C DP AltMode.

DP++ seemed to work fine on my Samsung S24 phone when I tried it after seeing that comment and was curious.

I've got a pile of passive adapters because I have an esoteric device that has broken DP audio but HDMI audio using DP++ works fine.