It makes sense as a literal translation of the controller function to the keyboard but not a practical one, which is also the case for how Elden Ring deals with your inventory. That's the Esc key's whole purpose in life! On a PC Esc should always be able to back out of menus, even if you wouldn't do the same with a Start button. Because Esc is used to bring up the menu in-game-which totally makes sense for a controller's Start button!-it can't be used on the keyboard to back out of options screens. Letting us rebind those options is an obvious first step, but more important is divorcing how they work on a controller from how they work on a keyboard. Even Dark Souls 1 let you change the menu key!
It also doesn't include an option for the map, which is hard-bound to G ('View' button on Xbox, touchpad on PlayStation). The key binding options don't include an entry for how you access the main menu (Start on a controller): It's hard-bound to Esc. This is a strange regression from all of the Dark Souls games on PC: there are some functions Elden Ring simply does not let you change.