To quote George Carlin (careful, swearwords ahead):
When I was a little boy in New York City in the 1940s, we swam in the Hudson River and it was filled with raw sewage okay? We swam in raw sewage! You know... to cool off! And at that time, the big fear was polio; thousands of kids died from polio every year but you know something? In my neighbourhood, no one ever got polio! No one! Ever! You know why? Cause we swam in raw sewage! It strengthened our immune systems! The polio never had a prayer; we were tempered in raw shit! So personally, I never take any special precautions against germs. I don't shy away from people that sneeze and cough, I don't wipe off the telephone, I don't cover the toilet seat, and if I drop food on the floor, I pick it up and eat it! Yes I do. Even if I'm at a sidewalk café! In Calcutta! The poor section! On New Year's morning during a soccer riot! And you know something? In spite of all that so-called risky behaviour, I never get infections, I don't get them, I don't get colds, I don't get flu, I don't get headaches, I don't get upset stomach, you know why? Cause I got a good strong immune system and it gets a lot of practice.
Carlin had a history of heart problems,[82][83] including heart attacks in 1978, 1982, and 1991.[52] He also had an arrhythmia requiring an ablation procedure in 2003, a significant episode of heart failure in 2005, and two angioplasties on undisclosed dates.[84] In the 2022 documentary George Carlin's American Dream, Jerry Hamza—Carlin's manager from 1980 until his death—said Carlin underwent many heart surgeries in a short period toward the end of his life. Carlin's publicist Jeff Abraham said that he once lifted his shirt after coming to a gig from the hospital to show Abraham his torso, whereupon Abraham said it looked like a science project.
Dude had his first heart attack at the age of 41, and lived four years less than today's median life expectancy in the United States.
Unfortunately there are people out there (a non-trivial number) who actually believe that kind of macho BS. Knowing that, Carlin's jokes don't hit the same.
I don't think that's a good argument. If I went this route, I would have to forgo Monty Python, Key & Peele, Mitchell and Webb, and god knows who else. There are always people believing this hyperbole, that's why it's funny in the first place.
But the good jokes either go extremely over the top, or actually have a joke part. The quoted one just repeats a thing that people believe. Reading it, I can't tell if it's supposed to be mocking the position, or is he a genuine grumpy guy complaining about kids these days and their cleaning.
I'm sure you can find the whole sketch on Youtube. I can only recommend watching it, unless you are allergic to swearwords - there are lots of those. Look for [George Carlin Germs]. But I guess the audience on HN generally knows how to figure it out by themselves.