In the area where I live traffic planners have shored up all the inefficiencies that led to those apps saving you time in the past. Road diets. Right turn only out of side streets with a hardened median preventing a left or straight route. Speed bumps. Downright punitive light cycle timing (I’ve seen almost 5 minutes before). You often fare far worse in fact taking those labyrinthine google maps/waze circuits through these residential side streets and shed time just sticking on the major arterials and highways.

I get the feeling these two systems don't talk at all.

I've used GMaps for navigation while on vacation in remote areas and the routing will be completely different than Waze, even when settings are made identical when it comes to time-vs-distance, avoid tolls, etc. Waze is much, much better.