If someone only has familiarity with AI from reading passing news stories, it is reasonable to think they would have such a perception of the field. I think your diagnosis of the downvoters might be correct, but "not even wrong" seems a bit extreme. AFAIK somebody out there is probably trying to do a research paper on simulated neurotransmitters as we speak. More interesting would be if anyone had links to existing research in that area. It may not be high-efficiency or high-performance technology, but as a learning tool for exploring theoretical models I think it could be very beneficial.

The topic reminds me of a book I read (and was fascinated by at the time), The Muse in the Machine by David Gelernter. It seems he has moved away from AI research and into political punditry, however, and recently made headlines denying that the moon landing ever happened. Nevertheless, that book contained a lot of exposition around the idea of creating AI with simulated emotion. This is simultaneously in line with the idea of simulating neurotransmitter function, but also has parallels with more general mathematical techniques that are in widespread use. Thus, the book (and perhaps the idea itself) are a bit dated, but I don't think it makes them less relevant.