It looks to me like the data was stored in a temporary cache and never got synced because the application crashed. It's an unfortunate experience, but not one that warrants a fearful take on Evernote. Things happen. I've typed a draft in Gmail before and it never got synced so I've lost it, but it doesn't make me stop using it. Maybe we all need to just take a deep breath and remember how it was before everything synced.
The note is over a year old. Maybe much more. The app should have told me something’s wrong. A red icon or a message. What if I had continued status quo for another year.
My primary assumption with Evernote is that everything is stored somewhere “safe”. Everything else is bells and whistles. It’s a bit like saying Gmail/Outlook is unable to send mails, and you are not informed.