I am of different opinion that these folks know they are wrong, but are too egotistic to admit it.

I was taught at an early age to accept mistakes, learn from it and move on. Now I have grown older, I realised that not many people know this, and society also stigmatises someone making mistakes. I think some people refuse to admit to be wrong because either they are too egotistic to accept and learn, or doubling down assertively on the wrong belief as a defensive mechanism from potential public humiliation.