This seems like a stretch. I saw my fair share of empty subway cars which contained within them an unpleasant surprise when I was there last month. Not conclusive, but “at all” is a very strong standard.
But the SFO phenomenon of open drug use, screaming disruptive people, and street level encampments isn't something you see really anywhere in the five boroughs, excepting maybe a few errant overpasses or very industrial areas of Hunts Point or similar.
Notice the comment on this thread about how in the poor areas it was unpleasant to get lunch? That attitude carries over. Starting with the fucking super bowl there was a very dramatic effort to shoo away the homeless people from where 'super bowl city' was. The net effect was a dispersal of homeless encampments the likes of which I've never seen. Combine that with stagnating wages at the low end and rising cost of living and you have a lot more people on the streets. Make no mistake, the homeless population in the whole of the Bay Area is growing dramatically.
Meanwhile in some "street photography" (but really mostly creep shots) group a couple people have been posting pictures of indigent folks from the 90s. The difference is pretty dramatic. From a friend who works for the city -- both meth and heroin have hit San Francisco very hard. The type of people that you see on the streets these days has changed.
San Francisco is also paralyzed by extremely aggressive NIMBYs. Shelters are at capacity, but the city's efforts to build more shelters (e.g. Embarcadero) are being battled by carpetbaggers. A while back the idea of "wet houses" was floated to get addicts off the streets (where folks will call 911 and tie up a large chunk of SFFD/paramedic resources). Of course that didn't go over well with the punishment first crowd.
New York is also facing record homelessness and is actually buying property to house homeless folks — San Francisco is…
This was a sharp contrast to the mid 1990s, when I lived in New York. I found aggressive panhandling to be more prevalent in NY than SF then, with panhandlers following me for blocks, approaching me at the counter of coffee shops (once crowding me as I attempted to get my change from the cashier, quickly picking up it up when I dropped it, and then asking me for it while holding it away from me).
I'm always a little skeptical about anecdotes, though, as the "homeless" population, ranging from non-addicted or mentally ill people who are temporarily without housing to severely addicted and mentally ill people engaging in criminal level harassment of people, often clusters in a few neighborhoods in a city, sometimes at the outskirts.
I met a man from Paris who refused to agree that San Francisco has a worse problem than Paris. He said that he believes that in Paris, the severe poverty is pushed out to the edges of the city. I don't know if this is true, or if he didn't want to criticize too much, but it is an interesting observation, at any rate.