> Can you use the time in a car while commuting to work to do the same?

Yes. In a well-designed city, a car trip will give you more time to do that.

> What makes a city "well-designed" in your eyes?

Not large, at most 300000 population, and designed for the needs of people, not for bike-lanes. So wide roads, plenty of parking (including parking lots), low density, large houses providing plenty of space, etc.

So your premise is that a city designed for cars is better for cars?

Just as cities designed for bikes are better for bikes, not people. Same idea.