I think this is the Acela corridor he was talking about. He probably misspoke when saying "a couple" - some people interpret that strictly as "two", while others interpret it loosely as "a handful" - but "most of these" implies that he meant the second meaning.
That interpretation doesn't make sense to me though. The Acela corridor is used for longer distance transportation -- anywhere else you'd simply fly. Neither has much to do with owning or not owning a car. I live in NYC, don't have a car, and I take any of bus/train/plane depending on where I'm going and if it's on the Northeast Corridor. If I lived in, say, Austin, I'd simply just always take a plane to any of those places, but my car ownership situation wouldn't necessarily change.
It's true that, along the Acela corridor, there are normal people who can't use the freeways to travel between cities for lack of car ownership. So the Acela is helpful.
Almost everywhere else that isn't the Acela corridor, people will have cars by default, so rail doesn't meaningfully increase access to inter-city travel over existing freeways.
This is where we still disagree. There are plenty of big cities that are not along the Acela corridor where people do not own cars by default (e.g. people living in downtown Chicago).
I don't understand your argument anyway. People own cars because they need them frequently for daily activities like commuting or errands. Infrequent longer distance trips are not the primary drivers of car ownership at all. If you don't own a car for your daily life then you certainly aren't going to own one just for the occasional road trip; no, you'll take a train/bus/plane in that case, or even just rent one.
Also, I live in NYC, and most of the places I go to are too far to drive to anyway. So having a car wouldn't be helpful. I'm renting a car in Las Vegas next month for DEF CON, but if I owned a car here I certainly wouldn't drive all the way there. I go to DC regularly, but even if I had a car I wouldn't want to use it for that trip as I find long drives unpleasant and would much rather read a book on a bus for four hours.
You can get to every significant Midwestern city on Amtrak from downtown Chicago. In fact, one of Amtrak's main weaknesses is that you often have to transfer through Chicago when it doesn't make geographic sense. That doesn't apply to Chicagoans. The Amtrak map is enlightening [0].
You can even do some train trips from downtown Chicago that make absolutely no sense in the era of flight (the rail tickets cost more than airfare and take 10x as long). I'd argue that anywhere you can't easily get on a train from Chicago is either too small to support rail service, or too far to be convenient by any mode except air.
There are a couple other places where people tend to live without cars, like the Bay Area. We already have good passenger rail service to Sacramento/Davis, and the SF/LA corridor is being developed.
>People own cars because they need them frequently for daily activities like commuting or errands
Correct, and when they already own cars, they already have easy access to inter-city travel (within distances that would be convenient by rail) via the interstates. Building HSR on these routes could provide a more convenient alternative, but the improvement is minor and incremental.
We need a massive investment in rail in this country, but we need it on urban and commuter systems. Inter-city travel already works almost as well as we could reasonably expect it to.
