Mantle and DiMaggio values will never reach Ruth levels. Never.
Ruth transcends sports. Mantle and DiMaggio do not.
Every single post-playing-days Mantle and DiMaggio ball is in a ball cube, and has been virtually from the moment it was signed. They are pristine, and will remain so.
Most Ruth-signed balls are in lousy condition.
Everyone who wants a high-quality Mantle or DiMaggio has one. Not so for Ruth.
Sorry, packs. Your kids ain't gonna cash in on the modern stuff.