Well, that was early 20's late teens Ritz...Dude is 36 now..Body isn't going to allow for the same gutzy performances you had when you were in your late teens/early 20's as you are as a 36 yr old.
I know a guy, who's currently in the Marine Corps. He turned 38 this year, made E9 already. Ran 16's for the 5k in basic training at Parris Island...Fast forward 20 years..He can't break 22 for the 5k. also, has a wife and 3 kids.
He still keeps in shape since he has to for his PT requirements, but a 38 year old body is not the same as an 18 year old body..
If he's fallen off that far at age 38, he's just not training very hard. I was a 17:30 5K guy at 25 and ran 19:30 at age 50. They're comparable performances.
Several weeks ago I ran a 5K at age 61 at around 22:30 and was beaten by another 61 year old who ran 18:30.
A 38 year old body isn't the same as an 18 year old body, granted. But that kind of falloff isn't about age or talent. It's about training.