I believe the problem is indeed “HDR-compatibility” though having read the spec just now, no TVs appear to be truly HDR yet as defined by the ITU, they generall

I believe the problem is indeed “HDR-compatibility” though having read the spec just now, no TVs appear to be truly HDR yet as defined by the ITU, they generally support the P3 colour space which is a subset of BT.2020. Citing Wikipedia for the statistics: In coverage of the CIE 1931 color space, the Rec. 2020 color space covers 75.8%, the DCI-P3 digital cinema color space covers 53.6%, the Adobe RGB color space covers 52.1%, and the Rec. 709 color space covers 35.9%. Technically DCI-P3 as used by projectors isn’t Display P3 as used by computers and smartphones but the numbers should give you an idea. What you want to look for is high rating for “colour volume” such as https://www.rtings.com/tv/tests/picture-quality/color-volume-hdr-dci-p3-and-rec-2020 https://www.rtings.com/tv/tests/picture-quality/color-volume... ... it varies based on LCD vs OLED. Even a fancy LG OLED might only be 87% of the DCI P3 colour space due to missing out on the brightest whites but absolutely nailing the darkest blacks in low light viewing.