Not requiring and not offering are two different things.

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.

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.