You are making very sweeping claims with next to no evidence (ironically, a very un-wise thing to do!).
The more I observe the more I understand good parents are exceedingly rare. The vast majority of parents fuck up one way or another. Which shouldn't necessarily be surprising, parenting is very hard!
Of course, if you're an adult of average intelligence, then 50% of parents will be dumber than you. Parents who are dumber than you are would not be rare at all.
But I'm not comparing adults with other adults. I'm comparing adults with children. I would be surprised to find a child that was smarter than their parents; it happens, but it's rare.
The more I observe the more I understand good parents are exceedingly rare. The vast majority of parents fuck up one way or another. Which shouldn't necessarily be surprising, parenting is very hard!