Sure you can refuse to believe the company's statement, but your comment is based on your (maybe deliberate, conveniently) misunderstanding of mail vs VPN...
Under Swiss law Email is communication which is subject to a VPN which is not classified as a communications medium and subject to different laws.
There is no way a legitimate company can insulate itself from legal compulsion. However a legitimate security company can do everything within the law to protect users. Proton does this and has been legally tested.
Your claim: they're just doing whatever the hell they want, whatever is "politically" expedient for them. Without any substance behind it.
Considering Switzerland's reputation as low-corruption country, i.e. having a government that follows the rules, I can imagine the VPN department will fight such a "request" as you say in their court of law, but hey, I bet your guts know it all.