Well, I took it to mean if you ever come under suspicion of a crime, the prosecution will look at your online social platform activity for clues to your behavior. This is happening a lot, many indictments are happening for the activities of January 6, and online postings are weighing in heavily in gathering evidence, for example.
so if you are being investigated by grand jury for assault charges and they find you posting about how you beat the crap out of the guy, well it’s a bit of a smoking gun.