You will still have to worry about expired SSL certificates in order for the WebRTC to work. Webcam capture works ONLY over a HTTPS.
Anyway what do you mean by "streaming webcams. No real server storage."? The original question was "can record video from desktop" - which is a bit different I believe.
You can uninstall the Videos module, disable all uploaders everywhere, but you will still need some custom module/software to be running in order to make streaming possible. So perhaps the messenger is the best option for your use case.