There’s an uproar because some users (e.g. technologically-impaired journalists) naively think their information is stored online secure from prying eyes.
First, the general rule of thumb is that anything stored online is not secure. Just ask the celebrities whose naked selfies were exposed in “The Fappening.”
Second, many of those complaining about Evernote’s policy change think nothing about using Google Gmail, Yahoo Mail, and other email services where machine learning is also supplemented by company employees viewing user content.
If you don’t want your stuff seen by third parties, don’t put it online. If you want to access everyday tools that make your life easier (like Evernote and Gmail), then understand there’s a trade-off that includes a loss of privacy.