Yes, there the few exceptions who were child prodigies - the likes of Vivian Cheruiyot - were outcompeting adults in their primary schools. Those that for example went to St's Patrick iten & Singore girls right from primary have the pedigree. The late bloomers are mostly liars. Kenya will eventually get banned.
Running is the most natural talent if there was one - and should pretty much show up - by the time you're like 5yrs. Zero equipment. Zero skills. Just running. So many of the current "great" athletes who went to school and has no impressive junior records. Those are the cheats.
The likes of Sir Mo Farah who are late bloomers are obviously big cheats.
Vivian Cheruiyot, in contrast, was already a big star in primary school - with her diminutive body - she uses to beat way older girls "At the age of 14, she pulled a surprise when she won the national cross-country championship in 1997. However, being underage, she was barred from joining Team Kenya"
I am starting to think doping has been a thing in Kenya longer than we think. That could explain why a lot of the athletes emerge on the scene and then quickly leave. The few holdouts are people like Eliud Kipchoge and this steeplechase roughneck Ezekiel Kemboi.