As NYC is an international financial hub, that's probably why (along with who mainly is in charge politicially [spending from more taxes] to some degree) things cost more than elsewhere in the US, similarly across most Western nations.

Whilst pick up trucks have been common in more rural areas for a long time now (because they were needed for lugging big/heavy things around on bad roads and/or use on farms), I think its just popularity along with SUVs that makes them very common over there now, even in urban areas. Many are indeed huge (as many of their 'ordinary' cars are - a Ford Focus would be called a 'compact' car in the US).

I'd bet you'd also find that outside of the well-off, many Americans run cars well into old age and proverbially run them until they fall apart. They also appear to see fresh oil far more often than over in Europe, probably because oil changes are far cheaper via indie 'lube bays'.

Even their 'bangers' and not-so-great US designed and made cars can easily last several 100,000 miles, at least from a mechanical perspective. Probably helps that they appear to value simple to run/fix cars, even if they are gas-guzzlers, because fuel has always been cheap, at least until recent times.

Back in the 60s when I lived in Canada and spent several holidays seeing much of the US, 'right-turn-on-red' was a local option, meaning that it was allowed in some towns but not others, which could be awkward. Another potential nuisance was that licence plates and licences were issued by province (or state), not nationally as here.

iirc right turn on red is not legal in all states.

USA is definitely not cheap anymore. Last time that I was over (2017) it was noticeable that prices had increased considerably more than just the slide in exchange rate. I have many US relatives, in many states - they all say the same. Of course what is important is what your money left after taxes etc. can actually buy you.

Also, in at least some states your vehicle insurance might cover only very limited amounts by our standards (esp. given their medical costs) - iirc Virginia actually doesn't require insurance at all (but you could of course be sued in court & potentially bankrupted).

8. The obsession with red rear indicators (effectively flashing brake lights) is purely a styling/fashion fetish. As car models are often restyled annually, the rear indicators may be red one year and amber the next, just as the rotating six monthly year marker (previously annual) on registrations help British and Irish drivers (not in NI) to keep up with or overtake the Joneses. Given that it's taken 100 years of motoring progress to get to virtually universal adoption of white parking/sidelights/DRLs (often rolled into one), even in North America, perhaps we can expect universal amber indicators front and rear a century from now!

I have lived in the US and UK and have driving licences in both. Last month I drove 2000 miles from Reading area to the south of France and back. In my own car. My goodness those French motorways are lovely!

1) Turning right on a red light is not allowed in NYC unless a sign specifically allows it. Montreal in Canada is similar. Elsewhere, right-on-red is permitted unless a sign prohibits it
2) Typical city speed limit Canada is 50 km/hr, although many are lower or higher. In the US it is 30 mph but with many 25mph. School zones are often 15mph (and enforced)
3) Undertaking is perfectly legal on multi-lane highways in both Canada and the USA. Large trucks HGVs are typically restricted from the fastest lane on three-lane roads (sometimes the two fastest on four-lane) but regulations will vary by state and even city. My observation is that the prohibition on undertaking is universally ignored in the UK now and rarely, if ever enforced. Middle-lane hogging is as common in the UK as the US (where it is legal)
4) Have you driven a proper Range Rover?
5) Yes. In fact, at one time, cars sold in NYC had to have horns that were less noisy due to constant use. After a while, you grow to love it
6) Roundabouts are common in some places in the USA. If you fly into Boston and head by car to Interstate 95, you will encounter two dual-carriageway roundabouts before you get there - if you survive... Boston traffic makes London look like Bognor Regis
7) No one knows. Macho men. Ask me about mine :-)
8) Probably because it was slightly cheaper and simpler? And works just as well? No rear fog lamps, either (unless EU-spec like fancy Audis) but TWO reversing lamps. No self-levelling headlamps in many vehicles that need them. c*** headlamps in general in the US
9) Lanes are generally wider, so less need to be precise
10) Lucky you. Same way I feel if my train from Reading makes it to Paddington. Almost as if I am blessed
11) NYC hotel rooms average US$500/night. Not as bad back when the Pound was worth $1.60 but really bad now. I agree London is less expensive. In the UK I can still fill a shopping cart for £100 (mind you, no booze or red meat). In the US, I can barely fill a handbasket

7. I didn't really understand what Americans use pick up trucks for. There were plenty everywhere and none was carrying any stuff in the rear loading beds.

You have a sedan for weekdays.

Your wife has a 'van' to take the kids to school.

You need a truck for the weekend when you don your lumberjack shirt and become a hunter gatherer. You might have a gun rack in it.