Well, speaking from sitting at the judging panel of 8 shows this year. Clearly it is not a fair statement to say YES they all do. That is just not true. Men's Phy is not a sport about the biggest, leanest and hardest. We are looking for the total package from the waist up. Presentation #1 requires no drugs. Good looks (Grill) require no drugs. So, now we are looking at the guy who has a nice spread between shoulder to waist. Then a great ab wall. Not hard and grainy. Not gaint. I see little guys 5'5" go up there with a great look. Now, all that being said sure some guys use stuff. That same dude might be a ugly cuss and still wont do well.
Here is the deal after guys do well at the local and state level it is time to go to Nationals. There everyone is bigger. Much bigger. I think then you will find a higher % of guys using.
So, please if you are interested in doing mens Phy. I suggest you focus on getting in shape. Still train the full body. Focus on presentation.
Here is how I view the sport. I'll see 20 guys walk out on stage in one class. In just a few minutes I can scan this group and find the best 3 or 4. After that it becomes a group of dudes in long shorts. Point is you either got that pretty boy look or you dont.
Guys ask me all the time. "Hey, GC how do you think I would do in Mens Phy?". I say have you looked in the mirror? Do you consider yourself a good looking dude? Most of these guys are my body builder friends. They dont do great in BB so they think men phy might be a better route. Answer: Nope stick to BB.
Not sure if all this rambling helps. I just wanted to be clear in the statement never feel you have to take drugs to compete. ALL sports are much more then any amount of drugs.
Best of luck,
GC