Xbox Series X Displayport?

If you have a monitor that reaches 60Hzz on HDMI and on Displayport 144Hz you can buy a Displayport to HDMI 2.1 cable so that you can use everything? As in e.g. Playing like cold was

I would advise against that.

Because HDMI is HDMI. With another connection you will not be able to achieve anything greater there, because as already mentioned HDMI remains HDMI. The type of connection or data transmission is different for Display Port, so you can't develop a pure HDMI to display cable.

It always has to be either HDMI, Display Port or some other connection whose technology is in the cable.