I think LA was naturally the best rider of his time physically and tactically. LA was outstandingly talented from a very young age (16) and he couldn’t have been taken drugs since then and (like Bettini) you shouldn’t dismiss his success without hard evidence.
If you believe in something, you will always find some evidence and witnesses to back it up (grassy knoll, Diana assignation, Fake moon landing, UFOs etc) but doesn’t mean its true.
If he took drugs it was because of the culture and to keep ahead of less talented people who didn’t deserve to beat him. If anything this makes him the biggest victim of them all.