When did common sense become so uncommon?

It seems like everyday I talk to somebody that has no common sense. Simple things that should be very easy to understand or figure out, are mind boggling to them. I felt like a genius explaining to somebody how to use the soap dispense in the bath room. Our conversation went like this. Me -See dude you just pull on the flap and the soap squirts into your hand. Him - That's pretty neat. Me - where are you from. Him - I have lived hear in Scottsdale for about ten years. I just walked out because I had nothing else nice to say. Has he been living under a rock, Or never washed his hands.
A buddy at my work thought he would tease the new guy by asking him if he had changed the air in his tires from summer air to winter air. The guy replied not yet should I get that done. Without missing a beat my buddy said yes, because they will be doing an inspection next week and that is one of the things they will be checking for. My buddy thought the guy would catch on there. But the guy drove over to the air pump let the air out of all 18 tires then started refilling them all with winter air. To make matters worse a manager pulled up as he had filled up about half the tires to ask him what the hell he was doing. He apologized for not doing it earlier, but since it had been so warm out he let slide. Needless to say he longer works at my work. But he took his CDL with him and is probably driving over the road trucks. No need to worry he isn't any scarier that the other ones on the road.
Just small examples of things that go on everyday. I think over time, technology has made us stupid.
smm