The new HDMI standard with a higher refresh rate will be welcomed by gamers. VRR (Variable Refresh Rate) decreases, in some cases eliminating lag during game play, while Quick Frame Transport (QFT) will reduce latency.
See also: All things you need to know about HDMI 2.1 standard
Quick Media Switching QMS will reduce standby time by black screen during media transfer. HDMI 2.1 also has Auto Low Latency Mode (AKKM) that automatically sets the ideal delay, for the smoothest viewing experience.
This is a comparison between the HDMI versions, making it easy to imagine the upgrade after every standard upgrade.
Comparison table of HDMI standards from 1 to 2.1
See also: Difference between HDMI and DVI