Most of us just want to fit in, and believe what everybody believes.
Coming to your beliefs this way is not actually intelligent. We don’t do it consciously. It’s just tribalism or herding instinct or whatever.
So if everybody agrees with you then that’s a pretty good sign that you are wrong.
Most people think the letter “A” is the first letter of the English alphabet.
Few people know that runes were first
You mean Cuneiform.
Not in the anglosphere
Assuming the English alphabet, A is the first letter.