Monitor reaction time not adjustable correctly?

I have an MSI Optix MAG271CR gaming monitor and play with it on the PS4 Pro. I use the included HDMI cable. Now I ask myself why I can't set the response time to 'fastest'. I didn't find anything on the internet. Thank you for the answers

Maybe that doesn't work with every resolution?

I don't know about it

I think that's pretty likely, but I don't know your monitor.

Try a lower resolution.