Considering the low taxes and lower cost of living in Zurich (yes, lower than Seattle), and the much higher quality of life, Zurich is a no-brainer.

I'd say if you get a job in the same company, Zurich is competitive. The problem is that if you lose your job at Google in Seattle there are several hundreds of FAANG positions and probably thousands of other 200k$+ SWE jobs you can reapply to. In Zurich you will maybe see a dozen of openings in the small subsidiaries of Apple, Microsoft & Co., and maybe some individual job offers from small AI companies, and applying to any of these positions basically means competing against the whole rest of the continent.

https://www.numbeo.com/cost-of-living/compare_cities.jsp?cou... says Zurich is 33% more expensive and I remember it that way.