I invite you to become a pentester for a year and see if you still reject this line of thought.
By running with loose tolerances and loose guarantees (and keeping systems as simple as possible) they remove the need for these tools - and their attack surface.
The action is stupid, but trespassing idiots get caught quickly - that's just "survival of the fittest" mechanics.
If you never trespassed in your life then you were probably not smart enough to get away with it?
As a kid I've tresspassed plenty, it often takes 'security' hours to even spot you
His comment says that small rural town water treatment plants don't have to run for 24/7. Not sure what you thought he was saying.
This sounds like it should be a punchline to one of those funny programming jokes https://news.ycombinator.com/item?id=25850739