I used to use it before the HDMI spec caught up, but they both now offered the same features for me (or so I thought) and the HDMI 2.1 cables I’ve got were thinner/easier to manage and hide so I swapped it out. I’m definitely gonna experiment later today and see if that’s indeed the issue, gonna be frustrating if it’s just patent/copyright garbage once again worsening user experience
Update: For anyone wondering, this was indeed the issue and I’m able to run 4k144 perfectly over DP. I really didn’t even consider that being the problem until now given the spec parity, very dumb move from the HDMI forum