I suppose they can't crowdsource that information or people would lie.

There must be a system for getting traffic information from municipalities to the road databases. Apple Maps told me there was no way to drive home a couple days ago, on examination the street in front of my house was marked as closed for the day, they were paving. That is essentially a zero traffic street in a grid area but bisected by rail road tracks without a crossing, so no one uses it except the people who live on it.