Access to nature from SF does require that you actually take advantage of it. There are probably a lot of young tech folk (among others) in SF who don't own a car and tend to mostly do urban stuff. In practice, if you need to rent transportation or depend on friends every time you want to go more than a few miles, you're probably not going to do it.
And at that point, you lose a lot of what makes SF appealing versus other cities.
As for weather, some people do value not having snow or typical summer heat/humidity (or both). But SF isn't the only place with a nice climate (and, for many, SF is gray and foggy relative to even other nearby California options).
For the purposes of the weather, I say that SF isn't in California. For better or worse. (During this current heatwave, I think better. Today's high is forecast to be 76/24.)
What are other options for similar mild weather? LA/San Diego gets too hot, Atlanta gets humid as well, Boston and NYC get too hot and humid in the summer, and are snowy in winter (though I don't mind that so much). Seattle's got too much rain.
I don't really disagree. Although a fair number of people are fine with the Southwest deserts, especially high desert.
But coastal California (which, as you say, is mostly somewhat different from SF specifically) is the only real Mediterranean climate in the US.
This particularly unpleasant spell of weather we had until a couple of days ago notwithstanding, New England generally isn't bad in the summer especially once you get out of the cities. You're rarely going to be too uncomfortable on the Maine coast in the summer even without AC. But, yes, it's cold and snowy in the winter.
Living in San Diego now and by the coast I don’t think it gets too hot (if you can the ocean, it’s likely not too hot). There is usually ocean breeze and most of the year it’s warm, not hot.
I do remember driving up the highway from Mountain View or San Jose many times and seeing this "cap" above SF. Literally going from short sleeves to jacket.
And at that point, you lose a lot of what makes SF appealing versus other cities.
As for weather, some people do value not having snow or typical summer heat/humidity (or both). But SF isn't the only place with a nice climate (and, for many, SF is gray and foggy relative to even other nearby California options).