The hypothesis we are entertaining here: things that humans have no experience with over evolutionary timescales tend to be bad for us. Ice cream for example, has more sugar, fat and salt than anything humans had access to until very recently; evolutionarily speaking, we have no experience with it. Ditto alcohol and heroin.
Nor is it a particularly well-formulated or convincing hypothesis, your cherry-picked examples notwithstanding. We don’t have evolutionary-timescale experience with medicine, electricity, the written word, or democracy either. How we think prehistorical people groups may have arranged their societies is almost completely irrelevant for modern policymakers, which is what this article is actually about. We have a long list of better ways to make this decision than “Hmm, well, how do uncontacted Amazon tribes of a few dozen people structure things? Perhaps we should just copy that in our nation of 300 million people?”