Size to strength correlation varies wildly. However size in no way equals strength. Pound for pound bodybuilders are not strong. They train slow twitch, muscles fibers. Which hold little performance value. While strength athletes train fast twitch. More performance, yet smaller in size. This is why there is training to focus on different fiber types. That's why there are different rep ranges
You make the same mistakes everyone else makes when arguing this. Like I said, you have to put everything in context. I said a big
ger muscle is a strong
er muscle, not that bodybuilder A is always stronger than smaller bodybuilder B. You can't compare two different individuals and then decide strength has no correlation with size. There are tons of factors that affect demonstratable strength. A small guy can be can be stronger than a big guy,
but both of these will be stronger if the cross-sectional area of their muscle increases.
Big bodybuilders actually are very strong. Pros in general are very strong muscularly. They will often destroy top powerlifters in nontechnical lifts. Of course a powerlifter will outbench a bb if he has practiced his arch while using leg drive to push etc. Put both on a machine and compare again.
Bodybuilders do not train slow twitch fibers, or do so very little. And even if they did, those fibers do not hypertrophy much so training would have nothing to do with their size.