[fpig]

The author's suggestion, as I understood it, doesn't prevent this, it only prevents them from doing it beyond a certain point in the future.

If you got an email that warrants "holding someone accountable", you would have plenty of time before the keys are released. So if you receive an email and call the police, nothing would change.

What you couldn't do it save it for years and keep it as blackmail material / until it's politically opportune to use. Of course it's not as clear cut as that, and an email may look harmless at the time, and only later, with more context, you might realize it contains evidence of misdeeds. So even a good faith actor might unknowingly sit on evidence.