Switzerland - as well as EU based providers - have to comply with court orders. And the EU as well as Switzerland issue court orders upon request from friendly foreign states ("Rechtshilfeersuchen" in german) - such as the US.

Wasn't Proton launched as a "your data is encrypted at rest, we could never access it without your consent"? The implication being that even if they received said court orders, they didn't have anything to give. Am I misremembering that?