In usability guidelines you often can find the rule to avoid links to the page itself, so called recursive links. Doing so the website usability and accessibility experience improves.
As default and hard coded in the core WordPress generates recursive links in navigation menus. Changing that into generating links except to the current post would break WP themes because they are built with style sheets based on link elements in menus.
So, to avoid recursive links without breaking earlier themes I recommend to toggle this function on and off, e.g. a checkbox labeled "Do not generate recursive links" under "Options".