[vueko]

The fact that rubber-hose cryptanalysis exists doesn't mean that cryptography is useless. While settings nerding is indeed probably of limited use if you have a direct encounter with authorities, settings nerding can prevent being caught up in a dragnet search for, say, every cell service subscriber present at a protest gone sour, just as ubiquitous cryptography probably can't keep you safe from dedicated NSA attention but can protect against warrantless dragnet fishing expeditions.

As pointed out elsewhere, the line between legal and illegal protest is very blurry and can shift rapidly; if anything, the only way to be sure you're not going to a protest that could eventually be classed as illegal is to never go to a protest, regardless of how pure your intentions are.