Which major US airports do not have train or public transit to the city center? Chicago does for both Midway and O'Hare, I'm pretty sure NYC does, not sure about others (not much of a traveler).
So, for instance, if I was in Koreatown I'd get the subway east to downtown and get the flyaway bus to LAX. If I were in Gramercy Park, I'd have to take 3 busses. When I lived in Culver City, I could get the Culver City 6 to almost to LAX and then had to walk or use a shuttle to get to the terminal. If I was in Brentwood, I'd have to get a bus to somewhere near Culver City, take the 6, then walk or use a shuttle to get to the terminal.
I'm not really sure what you'd call "city center" for a city like LA, but no matter where you are, there is absolutely positively not convenient transit to get you from there to LAX.
SFO's connection to Caltrain is this ridiculous jumping of hoops through BART. (There's a more direct connection, but still through BART, but is never running when I've needed it…) (BART also isn't at the airport, but rather, nearby, there's a tram to get there. So tram → BART → Caltrain…)
The point of an airport is that it's a major transportation hub, connecting the city to distant points. But it's a transit hub, and it should have that positioning on the local transit lines: a direct transition from that long-haul aircraft to city-level backbone transit. Instead, in most places, the airport's position on the transit system is best described as an afterthought.
I should be taking the taxi/Lyft/Uber to get to the nearest public transit station. Not "it's not worth it, we'll just taxi/Lyft/Uber all the way there."
I don't know for sure but I suspect the history with the Boston Airport Blue Line stop is that before a lot of the skybridge and other work done around the time of the Big Dig is that I'm not sure you even theoretically could walk between arbitrary terminals. So there wasn't a good central location to put it. Therefore, it made siting the T stop somewhere convenient for the planners given that Airport isn't a terminating stop as it is at a lot of airports a good option.
The Silver Line has worked fine the few times I've taken it even if it is a bit odd. But I live way west of the city so I'm not usually going from downtown to the airport.
Not sure why connection to Caltrain matters, as BART itself has about 7 times more daily raiders and connects to more places.
But these can involve multiple mode changes, can be awkward with any amount of luggage, and can take a long time. I'm guessing there is some "don't need to take a taxi/Uber" option in most cities but there are definitely airports like Las Vegas and Dulles where it's not very practical. (And of course it depends on where you're going within the metro area which isn't always the financial district or whatever the official "downtown" is.)
So if you wonder why for instance the light rail in Santa Clara county passes 100 feet from the airport. But the nearest stop is a mile and a half away, that's why.
I only know this because congress very recently repealed that law.
JFK’s story isn’t great, Jamaica and the LIRR aren’t designed for tourists, but it’s much better than LGA.
The real issue is that tourists just go "oh I should use the subway", partially because the LIRR doesn't obviously say it's going to Manhattan in the Jamaica terminal, partially because people are way more familiar with the subway, and partially because the fare is much lower (~$7 lower during peak hours). That connection is bad.
Ended up asking a random stranger if they wanna pool and split the taxi fee - he initially freaked out a bit, but then 5 seconds later agreed to it. Had a nice conversation and they ended up paying for it...