Well, they do slow down racing thoughts and "treat" grandiosity and other symptoms of mania that make me feel like a genius. I don't know if that's false IQ and on meds I'm returning to my average IQ or I'm lower than what my stable IQ would be without meds.
Before diagnosis and meds I was a math major, first semester I was in calc I and got an A. Next semester I took calc II I was on a bunch of meds after hospitalization including some sort of injection I failed the class. The professor sucked and calc II is harder than one (obviously), but I still blame the meds for doing poorly and the bipolar overall for dropping out.
I tried to go back to college, recently took a single philosophy course at the local community college and some days I didn't process a word my professor said and other days I understood everything and even felt he was going too slow or not going into enough details. I think that's more from just having good days and bad days though, but it makes it hard to figure out if my meds are making me more stupid than pre-treatment me or what.
They probably take the smart ones that "will rule the world" and convince us we're crazy so they can medicate and THEY can stay in control. I have a working theory that they intentionally cause eating disorders because they want to murder people and look like they're helping at the same time. Going off track here but I feel like someone should know so I'll keep it.

Short answer: yes.