Hello, I have exactly the same problem with 2 U2723QE monitors (both have same issue).

This happens with different devices: PC, MacBook Pro, Dell Precision

There is no mater it I just run computer or I am switch between two inputs. It also happened when some application need to change resolution. In my case the issue appears on USB-C and display ports.

Because it happened on two monitors it completely exclude issues with cables because there have two sets of cables and the problem w as also on originals cables included to the monitors.

Because I am using MB Pro I do not use daisy chaining feature.

From my point of view it looks like the monitor's software is freezing.

I forgot, I have HDR set on.