Your observation about Hugh Jackman is on point. If you need more evidence, look at the difference between The Rock (a pro wrestler and admitted user) between 1993-2003 vs. now. In 2021, he’s at least 20 years older, and yet his latest action movie appearances have him at a lower body fat, and higher muscle mass % per height than when he was 20 years younger? Come on, that’s not how biology works.
If you go to any serious website or forum where actual steroid users converse, none of this is shocking news. Drugs make for fast body transformations, and the results revert back to natural limits once you stop the drugs (useful for an actor preparing for a movie/show/appearance, who then does not care about that look once it’s finished).