If you spin the image 180°, you'll see another "no through traffic sign".
A car going down 15th in the 100 block is either local traffic to something 1xx 15th, or either block on Lake; or is going to be doing a U turn to get back to California.
A car going down 15th in the 100 block is either local traffic to something 1xx 15th, or either block on Lake; or is going to be doing a U turn to get back to California.
Playing with Google Maps, it seems smart enough to not route me on Lake. So I guess Waymo's route making software doesn't use all the information that Google Maps has, such as slow streets.