I've had two new monitors in the last 6 months.
One is a 4k 6hz and the other is 1440p 144hz.
Neither, at least for me, felt right straight out of the box.
It took some time and patience to find the sweet spot, and it is still not necessarily what someone else may find as their optimal image.
Some people prefer a darker image, others brighter, some like sharpness, others less so, some people sit close to the screen, others futher away, some may have varying degrees of colour blindness, or be short/long sighted.
All of these things can affect how you will want to set up your monitor.
Which is fine, as nowadays there are numerous ways to personalise the experience and tailor it exactly to your specific needs.
My point being, there aren't really any definitive settings that can be used by everyone.
The best thing is take a few minutes to play with your monitor, learn it's Interface, and find what is best for you.