DRM I don't like. But authentication to reporter, recording device, etc would certainly be useful. Plus proof of integrity.

Maybe also cross-linking chains of trust with nearby devices. So devices corroborate each other.

There's an analog hole here ... what's to stop me using a trusted camera/chain/everything to take picture of an 8K screen with a fake image?

(Canon had a "trusted" model as such. It was broken, IIRC by elcomsoft, shortly after release).

Or a Potemkin village.

A camera that shoots 360°, saves coordinates and date, would make it harder.

How could it tell coordinates in either space or time? non-military-grade GPS is spoofable (not really easy yet, but easier by the day) and GPS signal is rarely available inside a building (and sometimes just under an awning or cloudy days, or near skyscrapers - GPS in NYC is horrible; mobile phone GPS are as reliable as they are because they take cell towers and wifi into account).

The important point is " making it harder " - but how hard is hard enough depends on the party in question, and for many important ones, the simple answer is "not hard enough".

The people in a position of power are already in the best position possible to abuse a root of trust like that.

Look at the TLS x509 PKI, its a total complete mess.

This is not a workable solution.

What would definitely work is a blockchain. It would definitely make sense at least for reliably timestamping video recordings.

Only if you also publish your video (or a hash of it) at the same time.