The first caveat or the second one?

Remember the original argument was "I think public transit will continue to dominate in parts of the world where it currently dominates" I'm taking that and strengthening it to a significant expansion of transit, but obviously not everywhere can do transit.

If the lanes on the road can fill up, you have enough traffic to sustain some busses.

In emptier areas that's a pretty different discussion, but importantly you still wouldn't need to design around cars. Slap in a very basic road and it'll handle all the cars fine.

If you need an alternative mode to get to public transit, it has already lost the battle. I can walk to my car in 20 seconds. I can carry many items in its trunk, making it worthwhile to make multiple stops on my journey. Public transit is not meeting my use-cases.