El K, we have said that there is a very big doping problem in Kenya that makes it impossible for us to admire what would otherwise still be a remarkable degree of talent and depth unprecedented in world history. There has not been serious testing in Kenya for very long and even the testing there was was largely announced in advance, subject to bribes and extortion with Athletics Kenya, and limited to urine testing. There is more now and it shows, but this is a big problem and needs to be acknowledged as such without going to the old anti-colonial excuse that the West, which gives large amounts of aid to East African nations, is out to get them. (Maybe Trump is, but that's not the Western norm). There have been well over fifty tests. This is not only a Kenyan problem. It is also an Ethiopian problem where there is more of a national doping system, also ready availability in country for pennies, very little or nothing in the way of national testing, and also control of athletes by shady European agents and doctors, many of them from Italy, the leading doper in the article you link, and the Netherlands, as well as Eastern Europe for Ethiopia, with its old Eastern Bloc ties (remember the Soviet era agent 10 Ethiopian athletes tested positive for?). Other major doping countries and regions are obviously the Eastern Bloc, especially, Romania, Bulgaria, Ukraine, and Russia, China in the recent past, Turkey, Spain, and the North African countries of Algeria and Morocco. American sprinters have a long record of doping in great numbers as well. American distance runners do not have a long record of doping in great numbers, though there have been quite a few questionable runners--Salazar and his group, the NOP, his older group, Athletics West, his athlete, Mary Slaney in 1996.
Asbel Kiprop was an extraordinary athlete who seemed to break the mold with his impossibly long, thin frame, who could move from the back of the pack to the front effortlessly and could win kicker's races and fast Monaco races. He was very likeable and affable. It's a shame but also it is a good sign that some of the top athletes of the last decade outside Russia are being nabbed finally. For too many years, it would be just the small fry, whether out of fear of loss of revenue or because the big fish had the money to beat the tests or bribe/pay extortion fees to the IAAF and their national federations.
2008 Olympic third place finisher, Nick Willis, previously elevated to silver, now ought really to be elevated to gold--maybe a re-test is in order, because this test will probably knock Kiprop out of no championships from the past.
If he were elevated to gold, that would make him one of the most decorated Olympic 1500m runners. Currently, he stands at #7 with a silver and a bronze (from 2016). Ahead of him are, among others, Coe, Keino, El Guerrouj, Morceli, and Makh Daddy, four of whom were probably blood dopers/epo users. Gold and Bronze would put Willis tied for #6 with Luigi Beccali of Italy from 1932/36.
https://en.wikipedia.org/wiki/1500_metres_at_the_Olympics