I mean it's like saying what's the point of a security feature if thing that feature prevents from happening isn't happening after implementing that feature.

Sure, there's some truth to that, but shoe bombs, underpants bombs and the two liquids bombs have never been tried again. If they did, they would set off their shoes and underpants in the "cattle maze", where there are several planesfull of people, and nobody has been ID'ed, or x-rayed or swabbed.

There's nothing magical about setting off a bomb on a plane as far as terrorizing a populace goes. Bombs in the mazes before "security" would be effective, as we learned at the Boston Marathon.