How can you possibly think the US military, or any sovereign country, will magically spend an extra $165B a year on meat a year if all of the current consumers magically go vegetarian? Who exactly is going to eat a bunch of extra meat? There will just be fewer meat sales, period, ignoring a short term price drop if everyone magically goes vegetarian on the same day.
Ultra marathons are an entirely different sport from the 10k, and even marathons. Obviously training matters, but we also don’t have to pretend all humans are identical and only training and grit separate them.