Earlier quoted context omitted.
Given Dropbox's absolutely glacial pace of feature progression, no it would not be easy. I mean, all of dropbox runs off of one set of private keys... https://www.dropbox.com/en/help/28
Dropbox works with the NSA to hand over customer data. You are absolutely right that something like this would go over like a turd in a punchbowl at Dropbox HQ.
Edit to add link to EFF ratings: https://www.eff.org/who-has-your-back-government-data-reques...