Storing and indexing keystrokes is unique, and it might even be useful, yes. However, this does not at all seem safe to store without user knowledge for every document created. What could possibly go wrong....
It's probably one of those situations where you'd write a "Diversion Report" for the security team where you talk about limited assets at rist and a huge investment in engineering resources.
FYI - this is a kind of 'biometric' leakage eh.
Your typing style is probably as unique as your finger print.
It's not shockingly bad, but probably something, under thoughtful review, they should take care of.
Edit: by 'no use case' I mean, no use case for long term history. Obviously there's a good use case for 'very short term' individual keystrokes.
Also Edit: the answer to this issue is not 'Don't worry about it, it's a low risk problem'. This is the 'slow boil' SV way of thinking that is seemingly benign, but not acceptable in the long run. The answer is: don't store personal data that is unnecessary. It's that simple. It doesn't diminish the product a single bit.
Storing the change vector is essential for collaborative editing in the moment. But the UI should highlight a Flatten feature as part of explicit Saving or Sharing actions.
File -> version history
That is just for the file menu. There are 7 other menus each with their own long list of options.