Some people may not know the policy, but those who are at risk of losing any significant number of miles because of not knowing is quickly decreasing over time.

The OP and others similar would have been anyone who had lots of miles pre-merger, then stopped paying attention and stopped flying. I would suggest that anyone who has kept on flying and earning recently is aware of these rules now.

It has been many years since the expiration policy went into effect. So the bulk of people who remain to be "surprised" (and very negatively, to the tune of 100ks of miles) by these new changes is well over by now.