I can't read the whole article, but I suspect the last bit of that sentence is doing a lot of work, though there is a difference in effective tax rate. I don't earn a lot more than $100,000 but I also bought a 1,700 sqft house ten minutes from work (not that that matters quite as much these days) for well under $200k. $300k in SF "feeling like" 100k here might even be overly generous to SF.

(and that's just an income tax; as the US does not levy a general wealth tax, its current effective top bracket is 0 per mille)