Because very, very few cities in the US have "good public transport", and even then they only have it in certain small areas. In NYC, public transit is pretty decent in Manhattan, and a part of Brooklyn, and that's it. Everywhere else it sucks: Bronx, Queens, Staten Island, the rest of Brooklyn, and everything on the NJ side (Jersey City, Newark, etc.).

What we need to do is build SkyTran.

It is so much nicer living outside a city compared to living in one.

That depends a lot on the city and situation.

If you live in a city, then you have far bigger problems. It's no way to live.

If you live in a suburb you have far bigger problems. It's no way to live.

(see, I can say the same low quality thing you did and replace city with suburb)

Living in a large city has many huge benefits. Density of people leads to diversity and density in entertainment and food. Density means that you will find large groups of people that engage in the same esoteric hobbies.