Thanks for your posting. Yes, I agree that the cancel buttons are redundant on most pages (as you can always click the back button of your browser or close the browser window/tab). That said, there are users who don’t know about the back button or prefer a cancel button for other reasons.
You can remove the cancel buttons via UI scripts if this is critical for you but this is not something we would recommend to deploy to all users. Details on UI scripts can be found below: