I'm catching up a bit on recent travel news and pleased to share/remind that Switzerland has dropped nearly all Covid restrictions that have been in place over the last year+. You can find the official announcement here:
It will no longer be necessary to provide proof of vaccination, recovery or a negative test or complete an entry form.
This should drastically improve the arrival experience to Zurich from United and other US airlines.
As of this writing, a Covid test taken 1 day before departure is still required to get back into the US.