Leo is still having issues with HDCP copy protection. He managed to figure out how to strip the HDCP with a splitter. Leo says that's a fortunate secret side benefit. Many of these converter splitters have that feature. Mostly from China.
But why is his TV so dark when watching live HD TV? He's done everything he can to lighten it. But it's just plain darker. Leo says it's because of Dolby Vision. His TV provider is sending out an HDR signal that the TV can't decode properly. If the TV supports Dolby Vision, make sure it's enabled. Many modern TVs will support HDR10, but not DolbyVision. So, this is a known problem. His TV has to support HLG.
Here's a good article that explains it.