What a ridiculous supposition. Terunofuji, Kisenosato, Kakuryuu, Harumafuji, Musashimaru, Asahifuji, were all ozeki or lower at age 26. All save Terunofuji needed years after that to improve their sumo enough to earn a promotion to yokozuna. The prime years of a rikishi's skills are not like the prime years of an MMA fighter or a boxer. Unless you mean to tell me that the 4 kilograms Harumafuji gained over the course of 4 years brought him to the optimal sumo body he had theretofore failed to build in a decade-long career, or the 1 kilogram Kisenosato gained made all the difference.
And "advanced technical skills" are continuously improved until they decline with age or injury; they don't exist in a binary sense as something one does or does not have. Sotogake isn't an unlockable on a tech-tree.