I was surprised to learn that in other developed countries, they are not nearly so universal. And in the United States there are other good options that may be equally good. Checking for fecal blood is the usual alternative (i.e. Cologuard).
Colonoscopies are more risky than people realize. They are also a cash cow for the doctors who specialize in them. This leads to the usual conflict of interest in health care that is all but universal in this country.
Here is an article from Scientific American that is worth reading if you think I am propogating crackpot nonsense:
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