Apple Maps directions also has an "alerts only" mode which will shut up completely unless you need to know something urgent (e.g. you are approaching a 60 km/h speed trap and going faster than 60 km/h).
If you have the watch it will gently tap your wrist shortly before each turn, and it displays the turn in a very clear, uncluttered way on the watch screen, which you can clearly comprehend without needing to take your hand off the wheel. I find this is great in rental cars if you have no phone mount nor CarPlay and you want to avoid needing to interact with your phone while driving.
Interesting, I haven't noticed this issue, but I use my watch on the same hand that changes gear (at least when I'm in a country that drives on the right, which is most of the time), so I guess I'm used to having that hand off the wheel fairly often anyway.
(Edited to add: I just went for a drive and paid more attention to how I use the watch with Maps, and I don't take my hand off the wheel if I'm just looking at the directions. Rotating it towards me quickly is enough to get the screen to wake. I have the Series 6 where the screen only dims and hides dynamic information when 'sleeping'. Maybe older watches where the screen actually turns off & on have a higher threshold before they wake?)
If you have the watch it will gently tap your wrist shortly before each turn, and it displays the turn in a very clear, uncluttered way on the watch screen, which you can clearly comprehend without needing to take your hand off the wheel. I find this is great in rental cars if you have no phone mount nor CarPlay and you want to avoid needing to interact with your phone while driving.