Certainly within the sport of jiu jitsu the more skilled opponent will win against a more muscular untrained adversary.
On a street fight the outcome is less certain if the weight and strength difference is large enough.
See early UFC days
Discussion
any given sunday. but any amount of strength is practically quite useless to the untrained. one thai leg kick and theyre immobile, same with takedown
Fundamentally, you’re right that skill is the biggest factor in the outcome.
Sure, a jiu jitsu black belt will dominate an average joe with some muscle. That said I would have my money on Hafthor Bjornsson if he ever got on a street fight with Zuck.