Statements like this make it clear that the author hasn't really seen must of the world or even America.
I'm open to disagreements, but I'd say SF has the prettiest surroundings of any US city. The only place I've lived I think was prettier was Rio de Janeiro. I can think of other places that are also very beautiful though, such as Salt Lake City or Jackson Hole.
I like to say the worst thing about San Francisco is San Francisco - everything around San Francisco is gorgeous! Muir Woods, Half Moon Bay, Sausalito - those are within a ~30 minute drive from where I live. The coastal drive north once you get to Stinson Beach might be my favorite road to drive on because of the views.
As for the city itself, I would absolutely give the edge to Chicago for their architectural designs.
What places do you find the prettiest?
But I would accept "not a major city" as ruling out Jackson Hole and Breckenridge, because in fact they are not major cities.
I might accept San Francisco as being above Salt Lake, but not by much. I might consider Seattle to be as good as San Francisco.
San Francisco is a city with beautiful natural surroundings but so is Denver, Boulder, Seattle, Jackson, Honolulu, Kahului, San Diego, Los Angeles, Anchorage, Salt Lake City, Sedona, Carmel, etc. Even if by city they mean a large city or metropolis, I would still argue that Los Angeles, San Diego, and Seattle would be in the same tier of beauty.
I don't think it's an unreasonable candidate for someone's favorite, but it's pretty surprising for the author to not recognize that this is both subjective and highly controversial. If I had to predict what people in America would describe as "the American city with the prettiest natural surroundings," I think cities with large mountains would score very highly.
I can see this argument. There are certainly enough interesting sociological issues in San Francisco regardless of whether you think it deserves the "most" qualifier.
San Francisco has the prettiest natural surroundings of any city in America.
I think this one is very hard to argue. It's highly subjective, so I don't doubt that the author believes it, but if someone were asking me where to move and told me that they prioritize beautiful surroundings, San Francisco wouldn't make my list of recommendations.
On the other hand, I kind of understand the sentiment of not appreciating a place if you grew up there. I'm originally from Miami, FL, and it took moving away + a few years to be able to appreciate the beauty of that place for what it is.
But yeah, this is a hugely subjective metric, and I think we should allow the author his biases there, even if we disagree.