Well, I ain't no rocket surgeon, but......
My non-JW family said I was too smart to remain a JW. It's not really the issue- too "intelligent" to fall for the crap.
There are some highly intelligent people that fall for it, but I know what you mean.
I know some really scholarly WT readers that examine the stuff and check it in their Bible and really know the doctrine.
But in the last moment of questioning, they resolve that "Mother" must know better than them and they accept it.
My wife got all her college training while married to me, from none to a master's degree. She has learned how to question
the status quo, but doesn't apply any of what she learned to the WTS. Absolutely will not do it. "They have basic Bible truths
that nobody else has." End of the story for her.
It's dangerous mind-control. It hits intelligent ones and stupid ones and those in-between.