Why would they ban voice-enabled cars and force people to hold phones? That doesn't make any sense.

If you cannot comfortably see the map while driving: stop, memorise fragment, then drive. Where you cannot stop, road signs are usually available. Most automatic assistants in cars say the instructions out loud exactly so that you don't have to look at the screen.

New cars already display that kind of information on HUDs. They're usually minimal, so that you do no see the whole map.

(PS. Please do not drive with a phone in your lap. This is extremely dangerous. Just stop and find your way.)