This paints an unfair portrait of the average American. It isn't that they don't care, they just aren't as technologically savvy as this audience.
Take the Edward Snowden leaks. John Oliver did a wonderful segment interviewing people about NSA surveillance.[1] If you ask an average citizen if they are for or against "Section 215" or "X-Keyscore", they'll fall back on vague national security scare quotes. If you ask them if the government should see your dick-pics, then they start to understand what is at stake.
In many people's minds, what the FBI is saying makes sense. What's the big deal? They want to access a single iPhone from a terrorist.
Teach people that it means their nude photos could be accessed by any law enforcement official and I think you'll find that people really do care.