As individuals will each have multiple records associated with them, one for each of their previous home addresses, the breach does not expose information about 2.7 billion different people. Furthermore, according to BleepingComputer, some impacted individuals have confirmed that the SSN associated with their info in the data dump is not correct.
If these posts are made in a relatively short time then it could appear as spam. I browsing New is my default and, on a couple of occasions, I have blocked a user simply for being too active and flooding my feed.