Earlier quoted context omitted.
It depends on how you calculate the cost. https://en.m.wikipedia.org/wiki/List_of_most_expensive_citie... https://www.atlasandboots.com/remote-jobs/most-expensive-cit... https://www.expatistan.com/cost-of-living/index
If you calculate unrealistically, yes, sure :) Day-to-day expenses are a tiny part of a typical budget. In most scenarios, housing, income taxes and transportation alone will easily cost you twice as much in SF compared to Zürich. As a software engineer, the salary difference should make up for it, or even reach levels that are unlikely in Switzerland. That's great, but for most people, I can guarantee you, Zürich is…
The point is that many things, including many things that “rich foreigners” use to do, are more expensive in Zurich than in San Francisco. For example [1] a hair cut is twice as much ($62 vs $30), a basic dinner at a neighborhood pub for two is 50% more ($74 vs $50), going to the cinema is 30% more ($18 vs $14), a gym membership is 30% more ($118 vs 91$), etc.
[1] https://www.finews.ch/images/download/Mapping.the.worlds.pri...
edit: in the linked document, monthly rent for a mid-range 2-bedroom apartment is 37% higher in San Francisco ($3449 vs $2520). However, the cost of transportation in its different forms is higher in Zurich.