Most people would not consider 4 athletes out of hundreds "a lot". But if you do, that alone explains the different conclusions.
I'm only moving the goalposts back to their original spot in 2012.
As an absolute statement, a handful of exceptions would render it false, but as a "general statement", it is neither "ridiculous" nor "false", but remains true today, despite the handful of exceptions since 2012. This is because exceptions do not break the general rule.
And I did not say absolutely ALL "Ethiopians and Kenyans and other top East Africans" -- the stated belief was not absolute nor exclusive. Indeed, as few as 2 Ethiopians, 2 Kenyans, and 2 other East Africans is sufficient to make the belief, as stated, true. (That was not my belief, but what it would take to render it false, as stated).
"other top East Africans" would imply that the Ethiopians and Kenyans were also "top", or else "other" doesn't make sense. In any case, you should read that stated belief as including only "top" East Africans, as the original goalpost. In general I don't find it surprising that athletes of the caliber 5 minutes slower than the world record would be tempted to take EPO in an attempt to reduce that significant gap.
Winners of Olympic medals can be highly unpredictable, as athletes like Centrowitz and Rupp are Olympic medal winners, but more dominant athletes like Radcliffe is not.
Judging "top" athletes by time is much more reliable than by medals, as we only include the best athletes when they are running their best, which is not always the case for medal winners at fixed events with limited participation like the Olympics and World Championships. This reduces a lot of the variability in the long term.
I don't argue against the science, coaches, and athletes, but have always argued that considering ALL of the science, and ALL of the anecdotes and beliefs of coaches and athletes are inconclusive, and fall far short of supporting many of the myths about EPO and top performance stated by reporters and amateurs and anonymous posters like you. That ship has never left the port.