Professional athletes who use steroids can't call themselves the best because they aren't using their own skill.
Steroid use of professional athletes is an illegal act and which could result into a large fine or jail time. A punishment appropriate for the use of steroids should would be permanently banning them from participating in professional sports.
When I found out Arnold Schwarzenegger used steroid I was very surprised. I thought he gained all of his muscle by himself. He eventually admitted to taking steroids.