4k playback from streaming services (Netflix) no clear answers so I ask here

So no you can’t crack hdcp in the traditional sense. You could spoof it or inject it via a device that can support it between your source and monitor. It’s a two way communication. your monitor has to also support hdcp and if it doesn’t get hdcp hand shakes it may decide to just go black.

Actually, my experience with bad HDCP handshakes is random digital snow. Remember analog white noise/snow on cable/antenna channels that don’t exist? It makes a comeback as digital snow if a HDCP handshake fails.

admittedly its been 6 months or more but the last time I read the documents it seemed like a bad HDCP handshake at 2.0 or 2.x should make a black screen.

That sounds more like a high error rate which didn’t get detected when determining the link speed. I had the same problem with some cheap hdmi cables, they could connect at the speed I needed for 60hz 4K but there would be sparkles and lines and other artefacts.

I assume a failed hdcp handshake would just give you nothing.