Suburbs are fine. We are in 2025, not 1925, there is no reason why work from home isn't an option for information workers and others who don't need to be physically on premises. You are completely ignoring how much that cuts down on traffic and would lower the cost of real estate, so more people who aren't millionaires could live downtown. We also have electric cars that have basically zero emissions, there is a technical solution for this; not everyone wants to ride a bus or train.