Connecting RICOH THETA Z1 with Unity

I believe that your solution with a server is much better. The motionjpeg from live preview is going to have a lower fps and lower resolution.

How do you get Unity to consume the WebRTC stream? Are you using a separate server for signaling or STUN/TURN?

There were a number of projects in the past using ntt skyway

Many years ago, RICOH had a web conferencing service that used WebRTC.