So here is the thing.
You say you want to believe in talent, but it looks like your belief in the powerful performance of drugs won't let you.
Recall one of the big takeaways from Salazar was that none of the NOP athletes were found to have doped.
The nature of Salazar's infractions indicate the non-implication of any NOP athletes: 1) Salazar's accessory role in Magness self-infusing too much liquid (contrary to Salazar's explicit instruction) containing a non-banned substance; 2) an email to his athletes about how to describe infusions (considered "attempted tampering" with the anti-doping process); and 3) "trafficking" testosterone for a questionable experiment on his non-athlete sons.
You say doping is powerful and hard to overcome -- this is the leap of faith that prevents you from believing in the young middle distance talent. While we have clear examples of the powerful effect of male hormones for women in events requiring physical strength, this is not so clear in any men's distance events for any drugs either separately or combined.
Farah -- the only obvious change in Farah was the development of an unbeatable finishing kick. See above the explanation for Salazar: no NOP athletes implicated based, not only on "never missed a test" type defenses, but after intense scrutiny as part of a deep investigation lasting 5+ years relying on "more than 2,000 exhibits, ... 30 witnesses and 5,780 pages of transcripts" "leaving no stone unturned". No NOP athletes doped. Ever.
Cacho -- you ask where are the great Spanish runners now? I ask where were the great ones then? I looked for great performances all time, and found that Spain couldn't even distinguish itself from other non-Africans of the '80s. Besides Cacho, and a few 2:09 marathoners, I found no evidence of any Spanish distance juggernaut, just a short-lived effort to be as fast as other non-Africans before and after them.
Baala -- Baala is a French runner of Algerian descent. Baala may or may not have been clean, but I think there is another, better reason that the fastest Frenchman, from a country with a secret dirty past, is a North African Frenchman.
You suggest accepting Jakob's performance is a "leap of logical faith", but it appears this is because you have already taken other leaps of faith in the power of drugs, because you have been "burned too much in this sport".