It does seem like it should be simple to avoid those. I can imagine it might be complicated if the model treats turns as instantaneous and only considers edges in the road graph as taking time.

I would love a road navigation tool that gives more options to modify the cost of various route features other than pure distance/traffic. To me, Google is too willing to give a complicated route to save a tiny amount of time. It makes the driving more mentally draining. I would raise the cost of all turns, stop signs, and intersections where I don't have priority.