Sorry, but ...
1) Why not speak about the italian coaches/managers who are the ones that made Kenya (and currently Uganada) a "superpower"? Ever heard of Federico Rosa or Renato Canova? Did you look into the connection between Canova and Salpeter (one of the athletes with the most ridiculous progression over the past couple of years)?
2) If you really think that Hassan and especially Klosterhalfen are a lap ahead of Dibaba and made a huge step forward under Salazar, then you don't know much about those athletes.
Just yesterday Klosterhalfen for example lost against Gidey, one of the "flying Ethiopians", while Hassan for example was only third in the London 5000 m Diamond League race behind two athletes from Kenya. Hassan hasn't won a gold medal at a global championships so far (as far as i know) and Klosterhalfen is far from a lock to do win a medal this year. Klosterhalfen already won a medal at the 2016 U20 world championships and in 2017 she was the youngest athlete ever (as far as i know) to do the triple of breaking 2:00 in the 800 m, 4:00 in the 1500 m and 15:00 in the 5000 m. Anyone who followed athletics already back then knew that she was a generational talent (espcially people in Germany knew that, because even back then many scientists were "shocked" to see how little lactate was accumulating in her muscles when she did endurance tests, the consensus back then was that they had never seen anything like that).
Since joing the NOP Klosterhalfen hasn't improved her 1500 m PB. She improved her 3000 m PB by 9 seconds and her 5000 m PB by 25 seconds, but we have to take into consideration that:
a) All her PB's were back from 2017 when she was still 20 years old and those improvements only look "insane" because she was injured last season, otherwise it is pretty safe to assume that she already would have been much faster than 8:29 and 14:51 last year (before joining the NOP).
b) When she set her 5000 m PB in 2017 it was with a massive negative split and even back then most people agreed that she could have gone around 14:40 with better pacing.
As far as i know Hassan also only improved her 1500 m PB by 0.5 seconds or so after joining the NOP and i wouldn't call that a massive improvement. I think what both of them have in common is that they shifted their focus towards longer distances/did more mileage and that led to big improvements in the 3k/5k, but their 1500 m PB's barely changed after joining the NOP.
Let me be clear: I wouldn't bet anything on Klosterhalfen/Hassan being clean, but if you think they are doped, then (at least in my opinion) you should assume that they were already doping before joining Salazar.
Do i think that there is doping going on in the NOP? I honestly don't know ... we hear a lot of stuff and i have no doubt that they use methods that are "semi-legal", but i am also not sure whether Nike would really risk having some of the high-profile athletes at the NOP being caught for doping (that would be really bad for their brand), of course this could either mean that they have "forbidden" doping or that they just make sure that nothing ever gets out. I think that if it is possible to become as fast as the kenyan/ethiopian athletes even without doping, then only if you invest insane amounts of money like the NOP does and i don't think anyone else is willing to do that, so if any of the top runners are clean, then in my opinion it has to be the guys/girls at the NOP. For me personally Muir or Debues-Stafford are much more suspicious, because they reached (almost) the same level as Hassan/Klosterhalfen without the same level of money that the NOP has and without being remotely as successful as Hassan/Klosterhalfen were at junior level.