What problem does this address?

Currently, there is no built-in way to add conditions to menus, such as displaying different menu items when a user is logged in or logged out.

Adding the ability to add conditions to menus will reduce the need for third-party options, and will be beneficial for users who need to create conditional menus (i.e. membership type sites).

What is your proposed solution?

This could be an option added to the navigation block settings.