I believe my letter to Tim Cook worked too!

MacOS Big Sur broke support for high refresh rate external displays for Intel Macs. It was the DSC feature of HDMI/DP protocols, 4 years ago. Everyone that had it working at 4k@144Hz in MacOS Catalina, got only 60Hz in Big Sur and later.

Apple Support / Engineering department had me to install Catalina, show that 4k@144Hz actually works, got a ton of diagnostic data and came back with "you may downgrade to Catalina as a solution" LOL

Wrote to Tim Cook, with case number and, wait for it, MacOS Sonoma had it fixed!