The problem, I think, is that every pro or amateur athlete that has ever been proven to have used steroids or PEDs, or suspected to use them, has vehemently denied it when the issue first arose. Some have even gotten into serious trouble or gone to jail by testifying under oath. So just their denials and lack of proof initially are not enough for intelligent and educated fans to believe they are clean. We do not owe them the "innocent until proven guilty" concept.
I guess this means people should now think everyone is guilty. This attitude no longer applies to just athletes. It is spreading to include many other professions. Many people in society are now being asked to take drug tests at work, or where they want to work, just to prove their innocence. It is in the news all the time. Factory workers, city and state employees, teachers, firemen, cops, air traffic controllers, etc. Not to long ago employers and employees didn't think like this.
The latest to make the news are the teachers out at Illini Bluffs who now are on strike. They do not think they should be required to take a test. Who is right or wrong? In my opinion, nobody likes to pee in a cup just to prove they are not breaking the law.