Not an idiot at all
I love watching Karl's shows and I do laugh at his blunt quips, but the guy is far from an idiot. He is 100% his own person and thinks for himself, he questions absolutely everything and doesn't believe everything he is told. What's idiotic about that? He seems a lot happier than most people who are conditioned to associate happiness with accomplishments, such as getting a good job, getting married, having kids, having a big house, etc. People who base their happiness on having and on material things are never truly happy as when they achieve one goal, another is put in place right away. That's what I love about Karl and why I find his view so refreshing, he's completely happy with his life and hasn't felt the need to follow the masses.
I especially love when he met that South African guy who became a millionaire/billionaire. He wasn't the least bit impressed by his lifestyle and questioned if the guy wanted that life because he saw it in a movie or if that's what he genuinely wants. The fact that Karl can recognise that proves he is not an idiot. As a society, we are led by the media and advertising to want to obtain a lavish lifestyle in order to be happy. Karl, in that situation, was more impressed by the surrounding nature in his hotel suite by all the luxuries.
The world would be a much better place if there were more Karl's in it.