U2723QE, flickering as soon as DP OUT is connected on macOS

I know that multiple monitors are not working because macOS does not support MST/Daisy Chaining over DisplayPort. Though I have a Linux Laptop which supports it and I want to use it from time to time.

Now the issue is, whenever I connect a second monitor into the Dell, the monitor starts to flicker. So whenever the DP OUT port is connected with my Dell, it becomes unusable with the Mac M2. This seems somewhat related to this issue on latest Ventura.

Did anyone try to connect the DP OUT port with their Dell & Mac? What is the behavior?

My understanding is that the 2. monitor should be mirrored. But what is happening right now is that the 1. monitor is basically becoming unusable as soon as a 2. one is connected.