Intelligence is not a superpower

[KorvinStarmast]

As an example, the number of nurses and doctors that smoke tobacco is way too high. And surgeons are known to be disproportionately risk takers and adrenaline junkies.

Smoking is a means of stress reduction. That nicotine strokes some nice bits of the brain. Smoked on and off for some years, but finally quit for good. The medical field is also somewhat infamous for it's incidence of drug abuse and alcoholism.
"They should know better."
Yeah, maybe. They are also human.

Here's the thing, though: there's no such thing as one "intelligence" trait in real life. What we label as "intelligence" or someone being "smart" is a variety of different traits that are sometimes related and sometimes aren't. An intelligence attribute in any RPG is just a mechanical abstraction covering some particular aptitudes.

*golf clap*

It really isn't. Almost all studies show that there isn't any significant correlation. Meanwhile there is a very strong correlation with perseverance (or "Grit").

On the outside of the door to my Commanding Officer's stateroom hung this quotation, mounted on a brass plaque:

Nothing in this world can take the place of persistence.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent.
The slogan Press On! has solved and always will solve the problems of the human race.
― Calvin Coolidge

(Mid 80's, but all I can say is that this has earned a place in my box of useful thought alongside Teddy Roosevelt's little bit about "It's not the critic who counts ..."

It is the moment you play a game that doesn't hold your hand quite so heavily, the DM giving the players the freedom to step outside the heavily built in safety boundaries of the design, to stick out their PCs necks and pull the guillotine level themselves.

Best DM advice I ever got was, regarding players,
"Give 'em enough rope.
Some will make a nice macrame hammock with it, others will hang themselves."

In AD&D you couldn't cast spells unless you had a high enough Int for that spell level, meaning that intelligence literally gated your ability to use magic. An intelligence of 19-20 was rated as "supra genius" and higher than 20 was "godlike".

In that edition you didn't get to boost any of your stats every few levels (Unless you were a Cavalier from UA ...) Comparing the numbers between TSR editions and WoTC editions has to take into account a few mechanical differences.