> but I reckon they're talking about ADHD rather than "bipolar" mind

I think while some of the people he describes may have ADHD, very few people with ADHD are this person. His description resonated with me as a particular archetype, one that often makes their way into grad school eventually. Often enough to be recognizable.

I also don't think the author meant these people are bipolar in a medical sense, but used "bipolar" as the success+failure designation, perhaps unfortunately.