I don't think anyone knows Trump's IQ score. But even if he hasn't added a one at the beginning of his account of it, as I suspect, I don't consider it a measure so much of "intelligence" as of something called IQ which measures some not-well-identified portion of the whole. William Shakespeare had a very different sort of intelligence than Isaac Newton and Charles Darwin, but they were all pretty smart. Generally, I believe the most important deficient mental characteristics of Trump are that he is a crook, that he lacks any sort of persistent empathy beyond his children, that he is extraordinarily defensive and that he shows no sign of constructive thought. But none of these things delivers a score.
I think Obama was smart in plenty of ways, but I think his underlying determination to avoid conflict, which is a kind of fastidious peace preference, very often resulted in him creating larger problems of conflict down the road. Crimea and the Russian intervention in the US election probably happened because Putin saw Obama's red line crossed in Syria and he realised he was an idealistic bluff who was risk and conflict-averse. Putin judged he could take advantage of this weakness.
I was troubled at the time and that chicken came home to roost. Bigly.
But he ain't president now. We are stuck with Trump and assessing his qualities, not comparing them.