Agreed. The Material Design refresh for Google Maps replaced a design that had clear affordances with a completely flat, static-looking view. I'm sure it looked great on some Powerpoint slide shown to the higher-ups at Google, but it was a disaster for actual usability.

People eventually accepted the clever and novel UX decisions in gmail, so you know Kevin isn't saying "figure out where not to be clever" for lack of his own cleverness; he's saying it because it's true.