Crutchfield has a useful article titled HDCP 2.2 copy protection and 4K Ultra HD TV: What you need to know if you’re buying a TV or home theater receiver that provides this salient warning:
With the popularity of 4K TVs, you’ll be seeing loads of new 4K source components in the next few years: 4K Blu-ray players and media players for sure, and eventually, 4K-capable satellite and cable TV receivers, too. Every one of those components will have HDCP 2.2 copy prevention. If you attempt to connect one of them to a 4K TV that doesn’t support HDCP 2.2, you won’t see a 4K picture. That’s the sad truth whether the content is streamed or downloaded from the web, or played from a disc.