Though the author enumerated the some of the subjective things that rolled up into “QoL” and SV suburbs objectively don’t meet them (eg walkability).
Right, so if you then downgrade from the Silicon Valley suburbs with their excellent weather, strong economy, ample cultural and education infrastructure and head to some other less attractive suburb in the United States you’ve gone even further down the lower quality of life rabbit hole.
Not universally. The author wants to live in a city, so of course they're not going to enjoy living in a suburb. It sounds like they'd be better off in an East-cost metropolis like New York instead.
They could also live in San Francisco proper, too, without being far from family.