If you were 240 you weren't at or anywhere near 13% bf bro, haha. That's more than Arnold Schwarzenegger's contest weight, a 6'2 professional steroid user who also has good genetics. It's far more than 6'1 Serge Nubret, who likewise is a professional steroid user with good genetics, and so on.
You're focusing too much on numbers. You can certainly get to 240 at his height with 13% bf naturally. In fact, 13% bf isn't that lean. Serge was only weighing less in Pumping Iron (1975) because he did porn and his punishment was that he had to compete at ~200 lbs. He was capable of being heavier. Long back story behind that but in the end he held a lot of bitterness towards Arnold and the industry. Your average active guy is at 12-13%. When I sit at 11% in the off-season, people refer to me as "shredded" even though to me that's not even close to shredded. I think most people just never work hard enough to realize their own potential so they don't think it's attainable.
***I will say this: it is only obvious that someone is using steroids if the muscle has a certain density and hardness to it that isn't attainable naturally. It's not the body weight you should be looking at.***
Genetics also play a huge role. There were plenty of guys I competed against who were open about gear use and no matter what they took and how hard they trained, they could never get their calves to even be half the size of mine. And I don't even train my calves. That's genetic.
I'm wondering if you actually went the 6 meal per day of lean meat/veggie route consistently while training hard and getting at least 7 hrs of quality sleep every night for years. I don't think you've tapped into your full potential yet. Are you ever in NY? I'd rather talk about this in person. A lot of this is very nuanced and I guarantee that unless there is something wrong with you (thyroid issue, etc), what he posted is definitely attainable without the use of drugs.
**I'm attaching two pics: one where I'm at 13% body fat in the tanktop. The other one was 8% body fat. Notice that I had less detail in the tank pic but more size, while I had more detail in the other pic but less size.
THAT is the trade off when you're not on gear - you are bound to lose size while dieting. But again, the numbers he listed at the bf he listed are attainable.**