It seems that right now PW only reads config from /etc/pipewire/pipewire.conf and fatally fails on any inconsistency. It should read all possible config locations in proper order (built-in/shipped defaults, system-wide /etc, site-wide /usr/local/etc, user-wide ~/.config) with overrides and don't bail out on obvious misconfiguration, potentially leaving system without audio support or more.

It may even have dbus runtime configuration interface for GUI managers that would not need to handle its files by themselves.