This aspect of pipewire, the possibilities of routing audio and video between applications and devices, should be amazing. It's not, because most apps try to do it themselves.
Give me an OBS where everything is a pipewire sink, and the result is a pipewire source. Give me Firefox that doesn't talk to cameras and microphones, but opens pipewire sinks for inputs and sources for outputs (this bit is already ok). At that point I've got a full studio setup with remote interview capability perfect for podcasts, audio or video.
Maybe this is all coming together slowly and I'm out of date, but last time I tried it was so frustratingly close but not possible.