"Nothing is at risk"? A level of security has been removed, so of course the risk level has risen. Phones get stolen, phones get hacked, people get observed entering they unlock pin for the phone. The passcode adds a level of security to the data stored in Evernote. I find removing it without warnung irresponsible.
I have compared it to my bank card. It's stored in my personal wallet and no-one knows my pin. No-one has access to it, as long as it with me. If the card gets stolen, I know that it is useless at the cashpoint without that pin. Unless the bank says "sorry, we had to fix a problem, so we turned off the pin requirement to withdraw cash".
"One can argue"... yes, but one can also say the users are (sorry, "were") already using and paying for this feature. Rather than being warned not to update and lose the feature, I got an e-mail telling me I'll be paying double for the priviledge from next month.