Gotta get your money's worth ...
While the HDMI 2.1 standard is a massive upgrade over its predecessor, there are still many devices that can happily use your ...
I don't really need this but... I have a 4k HDR 144hz display (LG C5 OLED) and I've verified that 144hz is turned on; and a GTX 1070 (that everything I can find says will do 4k HDR at 144hz over HDMI) ...
It was a once-good idea that's never really gone anywhere.