It would only stop pirates for a whopping 24 hours at best. If there is a will, there is a way to bypass video DRM. It has to be decrypted at some point to appear on a display, and that's the place where it's possible to bypass any DRM without much issue. HDCP is useless [1][2][3], and unless Roku is failing to implement it right, my basic HDMI splitter from Micro Center is more than enough to strip it and feed info HDMI signal into a raspberry pi for ambient light effects. And in order for people to actually use ATSC 3.0 encrypted streams with an overwhelming majority of TVs on the market in use, folks will have to have some form of HDMI box that does the decryption anyway...

[1]: https://en.wikipedia.org/wiki/High-bandwidth_Digital_Content...

[2}: https://en.wikipedia.org/wiki/High-bandwidth_Digital_Content...

[3]: https://en.wikipedia.org/wiki/High-bandwidth_Digital_Content...