Pipewire offers different ways of interacting with it. There are compatibility layers for example for pulseaudio and Jack.
This is a good thing imo. That way you have compatibility, but aren’t held back by legacy interfaces.

Not requiring and not offering are two different things.

The qemu pulseaudio support wasn’t very good though. Very finicky to set up, and a lot of stuttering issues. Maybe this was an opportunity to implement something better with pipewire.