> I understand the complexity and difficulty of researching the subject, but this entire article is no good and is hardly applicable to most of the population IMO

Most of the population is untrained, and in many countries a majority is overweight.

I don't think your concern about "correctly assessing their 1RM" matters either - if anything that means the loads are even lower relative to actual 1RM, and their subjects were still getting results.

It may not tell us much about outcomes at the top end, but more knowledge of what advice to give "most people" is important, and if they can get good results at low percentages of 1RM, it seems a lot more likely you'll get people to try.