Speaking of low IQ, people are saying "Edmonton ruined him". Er... no.
The Oilers' drafting has (basically since 1982) been a disaster, but player development is a different issue. It's easy to look at it now in retrospect (with 4 more non-playoff seasons in-a-row in the future after 2012, and 6 of 7 seasons after Yakupov's arrival) and say, "They rushed him in too quickly!" "They didn't let him develop!" But I bet at the time, back in autumn 2012, if the Oilers hadn't played Yakupov in the line-up, 95% of you would have been on here castigating that decision.
So, yes, we can say now that probably one year in the AHL would have benefitted Yakupov's overall development... but then again, maybe not? In his rookie NHL season, he led the Oilers in goals, and he had a great relationship with a coach he trusted and respected. If the Oilers had sent Yak to the minors for one year, then he would have arrived as an NHL rookie in 2013-14, with his first head coach being... Dallas Eakins.
Anyway, the Eakins hiring was obviously a disaster that did not work out, and that's on the Oilers' org. But around this same period the Oilers also drafted and developed Jordan Eberle, Taylor Hall, Tyler Pitlick, Ryan Nugent-Hopkins, Oscar Klefbom, Jujhar Khaira, Darnell Nurse, Leon Draisaitl, Connor McDavid, and Ethan Bear, and I'm not aware of any "development problems" with these players. Many exceeded expectations, and three won the Hart trophy.
Also, Yakupov has had almost a decade since he left Edmonton to (re-)establish himself, and... he's done nothing of note for St. Louis, Colorado, or in the KHL.