In the backend go to Help -> Start Here / Joomla Help and then scroll down to My Profile. The help page there was created (by me) at the Joomla 4 RC stage and subsequently copied to the equivalent J5 Help page. I don't think that the COM_ADMIN_HELP_MY_PROFILE string is used anywhere in the Joomla code. Removing it should remove the reduntant item in the list of Help pages.
The MOD_MENU_USER_PROFILE string has the same content (My Profile) and again I don't think that is used anywhere in the core code.