That's certainly one way to look at it, but with the last hard fork, posts can be edited after payout (even though the steemit interface doesn't currently support it). I've been told it will eventually (and there are always the piston tools which can be used).

When it comes to the privacy I'm talking about, it has much more to do with sites you visit outside of Facebook and Twitter. Any page with a button on it is setting cookies and tracking your browsing activity. That's far more intrusive to privacy than the content you yourself willingly contribute to a social media platform.