Eh, maybe this behavior was changed, but PipeWire works in the same way ATM:

"The PipeWire configuration template file is located in /usr/share/pipewire/pipewire.conf. You can copy and edit the file to /etc/pipewire/ or ~/.config/pipewire/pipewire.conf. Since 0.3.45 you can also copy fragments of the config file to a file in the directories /usr/share/pipewire/pipewire.conf.d/, /etc/pipewire/pipewire.conf.d/ or ~/.config/pipewire/pipewire.conf.d/."

TBH, while this is a common pattern across Linux applications, the thought to look for override location in the /home folder comes solely from experience and I am not aware of any place suggesting it. I tend to treat all of root as if it was an immutable file system that is a hassle to edit manually. Saves a lot of headache.