Kipchoge is doing what even dopers have been unable to do. The sport is dirty from top to bottom. His pacers that got caught weren't the only ones even in their phalanx that were doping.
Whether or not he is doping doesn't even matter. Again, we're following a sport that forces us to suspend doping allegations. The best are probably on something. Give the same drugs to a skilled East African and he doesn't do what Kipchoge has.
The drugs have been given to the Americans and that still hasn't made a shade of difference on the world stage.
Drugs or not, Kipchoge is the GOAT. And, FWIW, I truly think he is clean; he would have gone down before he surpassed Bekele if he were dirty