Jeez if you have to go back 70 years to find an example that should tell you something.
Broaden it out and have a think. How many 19 year olds on the world stage start for the biggest clubs at CB? Now and going back decades. I'm not saying name them but just think how difficult it is to find any. Basically Varane. That's who comes to everybody's mind.
Yoro might be a one off but that's not how you plan. Nor has he really shown he's one of those freak teenagers who just already has it. Pretty sure at Lille it was his CB partner who did all the proactive defending and you can already see that in his limited game time here.
We have two CB's in their prime and play three at the back. It's nowhere near enough.
Even in the 90's, playing two at the back we had Stam, Johnsen, Berg and May. Whatever their quality what's clear is that in that position you don't rely on youth. You need dependable players, players who you know what you're getting 8 times out of 10.