I skimmed the video and read this article on t-nation. The gymnasts Sommers is talking about have been training for 5-10 years minimum. That much time for a maybe 2-3x deadlift isn't all that great. For most people, a 2x deadlift is fairly easy to achieve within a year.
I'm not saying gymnastics is terrible for strength, because the results are there, but for any random person, they're going to get a lot more mileage out of primarily free weight training and gymnastics on the side if they want to be able to do some admittedly impressive movements.
I think it is super important to note that in the article he said he nor the gymnast never even trained in deadlifts a single time prior to that. Doing a 3x deadlift first time seems incredible to me, even in a strength trained individual.