I did mixed martial arts for 10 years and sparred with someone who eventually went on to be a semi finalist on The Ultimate Fighter. He easily destroyed me and he couldn’t make it in the UFC. How much more of an outlier is Khabib or Mcgregor? I did Ph.D. studies in mathematics at a group 1 reasearch imstituion. Went to a talk by a graduate student from Berkeley in the same area as me and in school for the same length of time as me. It was clear I would never know as much as him or be as good as him. I quit my Ph.D. program shortly afterwards. I knew I wasn’t good enough to do worthwhile research in math. Outliers among outliers.
That being said, I agree that you'll learn much more from reading books, taking a course, etc. than sitting down and watching sports for the equivalent amount of time.
I'm not sure that's true, game tapes - if strategically cut together - can be very effective in teaching strategy and individual techniques for sports. Video games can also be very effective in this regard. This works because it activates mirror neurons when you imagine you're doing the thing you're watching.
If you're looking to build expertise in a given sport, I agree that watching it is probably one of the best ways to do so.
Instead of thinking "what can I get?" just revel in the players own sense of joy and mastery.