the reality, me think, is cheating still goes on, but now much harder to cheat.
As for third world countries like russia, they are being caught out too often. That is why they are being banned.
How else can you have the system?
Oh, everyone is cheating, so let us not punish the stupid.
Fact is testing is getting better all the time, and banning third world countries in terms of testing is the right way to go, as should be the case for any country found guilty of systematic cheating or turning a blind eye.