So historical cheating? I think every country has examples, but surely those caught are not the same as those who are probably cheating and get away with it, isn't that the point? I've also no doubt that all sport has hidden cheats that got away with it.
The issue is current Chinese irregular results, some of these athletes have twice failed drug tests. Do you think CHINADA is impartial? I certainly don't. It's China ffs. Chinese people don't even know about these allegations because they are completely censored in the country. But at the same time there is political posturing between WADA and USADA/US government because it is Chinese athletes, no doubt.
So you have a recent upturn in results for Chinese swimmers running alongside some very dodgy looking results that CHINADA has said are OK, and WADA has backed them. The Americans, imo rightly, are concerned about Chinese influence over WADA (because they'd rather have this position). And this is a country that has systematically doped before, in the 90s with the same sudden upturn in results, a country who have previously applied state-sponsored doping. A country who employed proven East German dopers to develop their swimming program back in the day. Forgive me for not believing this country.
So it's quite easy for the Chinese swimmers under scrutiny to pose with their gold medals and post "haters gonna hate LOL" on their social media but we've seen this all before, these are genuine concerns. It's not all east v west power plays. Russia systematically doped. China may be doing it too in certain areas. But in a country of a billion with their methods of coaching they will have some talent for sure.