There might just be a market for this
If, for those expressly wanting a "digital witness" in their home as part of a security setup, you could elect to have any reasonable evidence made available in the event of a suspected crime, this could be useful, a bit like the dash cam in your car.
I used (circa 2000) to want the security company monitoring my home alarm to be able to view internal cameras so that if they got an activation and I was out, I didn't have to return home or get a key holder before the police were called. Of course their link would have been activated only by a switch triggered by alarm conditions, not available to them 24/7, but it never came around. Now that tech has changed, this might be an option.
That said, I appreciate the concerns about mission creep, abuse etc and would not rush to be first in the queue until sensible people reviewed and approved the privacy terms.