No, I wouldn’t say so. There were some really bright people in my congregation. Two elders I liked a lot, both converts in the 1970s, with their wives. One was a heating systems engineer for hospitals who also like to quote David Hume. He had a very technical mind and was friendly too. The other was an electrical engineer for a large organisation. He could mend anything. Both their wives were bright too. There were other very intelligent sisters, including teachers and nurses and civil servants. There were former drug addicts, and they were intelligent and thoughtful people too, and turned their lives around after becoming JWs. Sure there were some odd characters and less intelligent people in the congregation, but it was a genuine mixture, including a number of interesting people from different backgrounds, in my recollection, though doctors or lawyers or academics are few and far between among JWs.
Through my association with Christadelphians, in recent years, I have come to appreciate that people in that community tend to have much better education and careers than typical JWs. Many are doctors and lecturers and professional musicians and so on. Unitarians are another step up on the social hierarchy, including senior academics, lawyers, and so on. Quakers are similarly middle to upper middle class, and include an inordinate numbers of teachers and lecturers. Seventh-day Adventists, at least in the UK, include a large number of immigrants from Africa who are doctors, nurses, and engineers.