If you've been involved in pro sports... you would appreciate the ubiquity of PEDs. I see it every day.
And if you're talking about a karate black belt, I don't give a shit. I'm talking about contemporary martial arts (a la MMA, wrestling is another good example). If you train with pro fighters or wrestlers, again, you would be forced to agree that PEDs are ubiquitous.
50%!? Try 85%+.
I know because I've seen it every day since Undergrad sports. I'm 34 years old. I still train and I still see it all the time. In the weight room and at the MMA gym. If you were/are there, you'd see it too.
The people who flip their lid over this stuff are generally people who don't know because they've never been in the sports world.