And this study only had 40 participants that were testing 3 different drugs. So only about 13 participants per drug. Again the sample size should be over 30 to create statistically significant results. If it's not over 30 individual variance in intelligence can wildly screw the results.

Personally as someone who takes modafinil, I don't use it to make me smarter. I use it to keep me awake and alert as I am working remotely and my company's 9-5 is my 4-midnight.

I have always used it as a wakefulness aid (for example when I was depressed and would get fatigue more easily). Sometimes it does get me buzzed but that's not the main purpose.