I'm not saying it's warranted, but I could see there being a lingering perception of "hey, if they were willing to hang onto all that art the Nazis stole for so long they'll probably stay out of my email."
My perception is that the general perception is that the Swiss have a reputation for neutrality, especially in regards to the contents of bank accounts and lock boxes.
Before continuing I want to make it super clear that I'm not endorsing the Nazi's stealing art/gold/whatever. With that said, were Swiss banks handing over assets to the Nazis that had been previously held for Jewish families, or were they only holding assets for the Nazis which the Nazis themselves took from Jewish families? (This question is not intending make one option sound more morally acceptable.) My perception is the latter, but I could be ignorant. If I'm not ignorant (in this domain), I don't see why these events would call into question the ability of the Swiss to securely hold assets.
That is, I think I read long ago that the confidentiality of Swiss bank accounts was compromised during WWII for the benefit of the Nazis. I thought it was common knowledge.
However, I seem to be having difficulty finding a reference with Google at the moment.