Finding Realistic Natural Bodybuilding (and Powerlifting too) Standards
Steroid use is much more prevalent in the US than people think.
A conservative estimate is 1 in 10 serious male gym goers are on steroids or have used it in the past. That's just based on a survey of steroid users in the US from 2010s and the number of male serious strength training gym goers. It is probably even higher today due to social media pressures.
There is only maybe 1 in 10,000 are naturally gifted. There was all this business about FFMI less than 25 or something "to prove" that people can achieve peak male physique naturally, but that is very very very rare statistically. It is more likely the case they just use performance enhancing drugs to get to that level and quit to maintain fake natty status. Like people would point to Eugen Sandow, but you have to remember that he was a CIRCUS FREAK, and I don't say that to be mean, but I mean to emphasize that he was so out of the normal that people would pay money to see him. Would you pay money to see regular people? These days, I don't even think that guy would be in the top 5% of muscularity or strength compared with what you see in the average gym.
If you apply Bayes probability on these numbers, its 99.9% certain anyone you see at the natty limit is on steroids. And so if it looks like they take steroids or PEDs then they probably do. If you want to have an idea what is actually achievable natty, look at the people who are 80-90th percentile strongest or biggest or leanest at the gym. They are more likely natty.
P( uses or used steroids | looks like natty limit ) = P( looks like natty limit | uses or used steroids ) * P( uses or used steroids ) / [P( looks like natty limit | uses or used steroids )P( uses or used steroids ) + P( looks like natty limit | never used steroids )*P( never used steroids )]
(0.65 * 0.1)/(0.65 * 0.1 + 0.0001 * 0.9) = 99.86%
* edit for typos, new to reddit sorry