Caveat: the following is all pure speculation on my part.
"Surely there must be insider knowledge of who is supplying the drugs, who is taking them?"
lol everybody knows. And by everybody, I mean EVERYBODY.
Everything is known by everybody on all sides of the issue. What continues to happen is a sort of group dance--people say things, people do things, people try things, it's all out in the open and announced, to give them all a chance.
What we see in Kenya represents a focus of testing resources, and an "OK go for it, we'll see what happens" response from inside Kenya. They don't much care, because the country, the clubs, the athletes, and the coaches all know that some will slip through, and that it really doesn't matter which one--but it is best if they are golden, like a Kipyegon, and become a darling of the scene. It is always tougher for track to shoot itself in the foot.
The various entities involved are feeling each other out at this point--capabilities, intentions, procedures, appeals, bribes, etc. We will see how it all shakes out.
Let me state this: pretty much any track powerhouse would have similar results if resources were focused upon them: USA, UK, JAM, BAH, CHN, NOR, TUR, ETH, NGR, RUS, RSA, various mideast and North African countries, NCAA, etc.. Things come and go, though.
There is nothing wrong with cleaning a bit of house, one country at a time. KEN was a good place to go, lots of low-hanging fruit with desperately poor and uneducated athletes manipulated by slimy Italian (and other) coaches and agents.
And there I come to the issue: the coaches and agents. The athletes are just out for a few bucks. Sometimes they make a big hit, then disappear. Most often they end up with nothing to show for their efforts 10 years later...but the coaches and agents are the real problem. They are not only the ones executing and facilitating these things, they are the ones who have the initial idea. It all starts with them. To clean things up, criminal penalties are needed for what amounts to drug offenses, and massive asset forfeiture and civil penalties to disgorge profits and make restitution.
Will those things happen? No, because it's complicated, and therefore expensive. Right now, it is easier and much cheaper to target the athletes, who in a perverse way represent the symptom rather than the cause.
Kenya is not special. Ireland was not special. Jamaica is not special. The USA is not special. The NCAA is not special. Ethiopia is not special. Russia is not special. Norway is not special. Nigeria is not special.
It's funny to see Kipyegon destroying doped WR's, while "the hammer is being brought down" on Kenya. The big news-making stars will not be touched, just like Dolt. They ARE track and field. Nobody outside the 10 hard-core track fans in the world cares about lane fillers. They don't even care who makes a final. They don't even know or care about the silver and bronze medalists.
Track exalts victory over competition--and the bigger the victory, the more exalted. A victory over all of track history is the ultimate insulation. Right now we have some untouchables: Kipyegon, Warholm, Mondo, SML, maybe Crouser--anybody competing, who holds a WR. They might be asked to dial it back a bit, but only after the WC. Look what has happened to SAFP and ETH--they have disappeared. You know why? Because at least one of them didn't dial it back as asked. Why not? Because they hate each other, and are fighting their own internal war--and because at least one didn't listen, they are paying the price. You will see.
Until we return to the honor of competition as a standard, track is relegated to a revolving-door clown show.
This is all pure speculation on my part, of course. YMMV