It's not arrogance, it's science.
I never washed one flight instructor out at Amflight.
Mappers, meat missile tossers, banner towers, you name it; they all had problems with basic attitude instrument flying. Did some of them make it through? Sure. But they didn't have the ability to self critique like flight instructors did, and they didn't have the hand flying skills that flight instructors did, and they didn't have the rock solid instrument skills that flight instructors did.
I don't know about you, but I want to be the best at whatever I do, and I don't like cutting corners.
So like I said, if you're ok with being mediocre, then don't instruct. If you want to be the best, then get out there and teach it. This is not a value judgement about what paths others choose, simply an elucidation of how to be great at something. If somebody doesn't want that for themselves, and many don't, then that's fine.
And that doesn't matter what it is in life, if you can teach it, you're at the top of your game. I mean why do you think they make the best of the best at any company sim instructors?