Thanks for the pro-train perspective.

1. agreed
2. America was built on the railroad because cars didn't exist. Changing cities from un-walkable to walkble is infeasible, cities are not readily re-configurable.
3. No it's not silly, trains have much simpler steering, stopping and starting requirements, they travel along pre-determined paths only. Cars are substantially limited to roads, but the construction of those roads can be relatively scant.
4. Most of the car industry will be dead before the decade, they're badly in debt and won't make the transition to EVs. EVs are a substantial step forward for the environment vs ICE cars. Cars provide time-freedom while trains constrain travel to predetermined schedules.
5. With self-driving cars vehicles can be shared as a service that doesn't provide a barrier to entry for poor folks. This is a predictable outcome of moving from a car-ownership model to a transportation as a service model.
6. Yes, hydroponics/aeroponics/precision fermentation will enable urban compression (and free up enormous previous agricultural land)... but MOST people want more space not less. I expect that the transition to a transportation as a service model will displace 2/3 of all car ownership along with 90% of urban parking spaces, this will free up about 1/3 of urban areas (where parking takes 1/3 of available space.

Suburbs don't exist without cars. Turning existing cities into walk-able cities is a non-starter...cities are not re-configurable. European cities that leverage public transportation well are dense. European cities have a density greater than about 5k per square km and are closer together than American cities. There is a population density threshold for trains becoming reasonably efficient. In the 1950s, when Americans moved from cities to suburbs that population density went away... and so did trains. In the US there 14-16 million people living in dense (>4k per square km) urban areas, that's about 4-5% of the US population. For the rest of the US trains are not cost/time effective.

When I have vacationed in Japan and Europe trains work GREAT (it was as faster than driving). When I've experimented with rail transport in the US outside of a handful of dense corridors (DC, NYC, next to BART lines in SF area), it sucks. The US does not have the geographic constraints that require Japan and Europe to have dense urban areas.