What does it do? Reduce problems?
Even the AMD engineer technician don't know what it is ...It just for advertising ( a blank option ), click on or off won't do anything ...Something like " turbo on/off switch " in your toyota yaris, where there are no turbo device in this car ...
Guess you clicked the 'More' in radeon display setting, then read hdmi link speed wiki.
That's all I can think of, I leave it off.
You could try asking https://www.amd.com/en/support/contact-email-form for a more in depth answer.
Under Display tab click on "more" and you will see the explanation of all settings:
Retrieving data ...