Found resolution 4096x2160 with 4096x2160 @ 24.000000 Hz
Found resolution 4096x2160 with 4096x2160 @ 23.976025 Hz
Found resolution 3840x2160 with 3840x2160 @ 30.000000 Hz
Found resolution 3840x2160 with 3840x2160 @ 29.970032 Hz
Found resolution 3840x2160 with 3840x2160 @ 25.000000 Hz
Found resolution 3840x2160 with 3840x2160 @ 24.000000 Hz
Found resolution 3840x2160 with 3840x2160 @ 23.976025 Hz
Found resolution 1920x1080 with 1920x1080 @ 60.000000 Hz
Found resolution 1920x1080 with 1920x1080 @ 59.940063 Hz
Found resolution 1920x1080 with 1920x1080 @ 50.000000 Hz
The thing that stands out to me is ^ that's an odd collection of resolutions for a modern AVR and TV to have. I'd expect to see 1080p @ 30/29.97/25/24/23.976 not just 60/59.94/50, and the full range of 4K (4096 and 3840) resolutions not a few (but again, not all) of the < 30 ones. To me that suggests something isn't right with cables/ports (or the configuration of ports) in the HDMI chain; and I'd normally point fingers at the TV side since AVR's generally default to mirroring the upstream HDMI capabilities to the downstream HTPC device (although they too can fiddle with things).
The curveball on modern PC boxes with DP hardware is whether an LSPCON chip is being used to generate HDMI, and if yes, what bugs the LSPCON firmware has, because they are notorious for issues - including the "but it worked in Windows" kind.