I share your opinion, but so far we were not able to convince the developpers to hide or reduce the size of the buttons.
See discission here: Maximize screen space for map display on Android Auto
BTW, “Follow mode” is in Kurviger a special mode which you can access only if there is no route loaded - it will appear where the “Navigation” button is. Quite inconvinent that one has to delete the route to access this mode, but that is how it works now.