For starters, it does nothing at all to prevent taking screen shots. Which is what this thread is about.

As for high quality video capture, it is trivially easy to do. How do you think high quality copies of Netflix-only content ends up on the pirate bay they same day it comes out?

Yes it does. HD Netflix in Chrome, Edge or Safari will result in black rectangle when you screenshot it.

Yes it does prevent taking screenshots of high resolution playback. Your options become low resolution capture or nothing.

High quality captures are still possible if you connect an external capture device coupled with something that provides the necessary drm authentication or you need a software based drm defeat.

Neither are “trivial” as you say.

An HDMI splitter completely removes HDCP, so if you want to do a hardware approach, that doesn't require any software at all. If you don't want to use some cheap product from amazon, just run Netflix in a desktop VM. Both of these options are very trivial to implement, no complicated software bypass at all. Also remember that for piracy to occur, you only need one person to go to this very small level of effort to get a torrent uploaded. These protections are useless, and achieve nothing other than bothering legitimate users.

Also, here's a screenshot I just took of a Netflix show (it's 1080p, but still...) https://imgur.com/a/evJjf06