As far as I know, the Playstation 5 currently only supports games in 4k or 120hz, not both. However, I read that Sony has released a system update on 22 April 2022 that allows game manufacturers to use a variable refresh rate. I own the monitor and a PS5 and always play in 4k or 120hz. Whether games can be played in 4k and at 120hz with the variable refresh rate, I don't know. I assume the variable refresh rate depends on the game. Information about the system update from Sony:
https://blog.playstation.com/2022...
