>search for Amsterdam from the 1970s for example.
Everyone always compares Europe to the USA. What works there is a non-starter in the USA because first, yes, we have a different culture, but also, the density in Copenhagen is way different than in most USA cities. It can work in some places, but not in all. Sure, in the city centers you can have the intersections, that's fine. But in California, like in Los Angeles, it is so huge that some people would have to ride 30-50 miles to their workplace. Because the USA is a lot bigger. Also I noticed in the photos you linked to that the streets are just one lane each direction. Totally a no go, it wouldn't work. It would be totally impossible on main city arteries.
However, even in Los Angeles, if you go down the side streets, there's hardly any cars there. Shit, I walk down the middle of these suburban streets with no problem. Not at 8 am or 5 pm when the commutes begin, but during the day there's hardly any traffic, even on the streets the next one over from the main city artery streets. Just about any bicycle rider should be able to get to wherever they want using the back streets - the streets off the main arteries. So it is a little out of the way and not a straight shot, but that's the whole point of riding a bicycle, is to be on the bicycle and also to get exercise, so who cares if one goes out of the way just a little bit. But it just seems like bicyclists want to use the main vehicle arteries....just because. I mean, even if you make these arteries more bike friendly, believe me, they will still be fantastically more dangerous than just taking the side streets. It's nuts. I only walk on the side streets everywhere, it's so much more satisfying than the noise of main arteries.
As far as Market Street in San Francisco goes, you can ride your bike down Minna, for example. But what I'm saying with San Francisco does not really have to do with bicycles. I'm talking about Muni, not bicycles. I used Muni for years, and it makes sense in a city like San Francisco. It is great - go downtown, you avoid d traffic and don't have to worry about parking. But this is not the same in other cities. It's ridiculous in Los Angeles, for example, which is spread out all over fuck.
Also, people always seem to compare to Copenhagen. First, it is their culture. We have a different culture, and I'm not even talking about cars vs bikes. But it is unfair comparison because Copenhagen is unique. You don't have this in London, or Berlin, or any other country. Copenhagen is an outlier, probably the only one.
And additionally, while super hardcore and super fit bicyclists might be able to ride anywhere in San Francisco, let's see a normal person take a bike ride up California Street from the Financial District to Pacific Heights. Good luck with that one.
>By just reducing the width of car lanes (which help reduce speeding) you can probably build bike lane in many US streets
It depends, but honestly, I don't see it. Like on Wilshire and Santa Monica Boulevards, no way, just no way. Those are the main arteries from the Pacific Ocean to downtown LA. Going down to one lane? Nope. Just impossible.
However, there are tons of suburban streets, that I mentioned that are a way better and massively less stressful for a bike rider. You have to sometimes zig and zag, but so what? It's a block or two to go around a park or whatever. This is in Los Angeles. And even in San Francisco, must of the city is suburban streets. Sunset, Richmond, Excelsior, Potrero Hill, Noe Valley and the rest - all of these you can ride on off the main arteries. But sure, downtown is always different. But bike riders are going to want a bike lane ALL the way down Mission Street, just because. No reason, except "just because." I mean, I know I'll always get pushback. There will always be, "yeah, but this and that."