Back when my dad started selling wine, there were only a handful of premium wineries in California, and the only model for world-class Cabernet was the wine from Bordeaux. Those wines were significantly lower in alcohol and less fruit-filled than their California counterparts. They were also very tannic, nearly undrinkable wines when they were young.
The concept of laying Cabernet down before you drank it and for ascribing inherent quality to a wine that can (or needs to) age before it is drunk is directly related to the Bordeaux experience. California wineries trying to make exceptional Cabernet emulated Bordeaux even when the viticultural conditions in their home state blessed them with a completely different kind of wine.
To my mind, the biggest, brawniest Cab in the room is not the prettiest pig at the Fair. Often, these huge monsters are so out of balance that by the time the tannins have softened with age, the piddling fruit that had started the journey was long gone when the wine was finally opened.
I love big, BALANCED wines. Cabernet is a grape that has tannin, and even more tannin is imparted to the wine when it is aged in newer barrels. Cabernet shouldn't apologize for having structure, but it also shouldn't haughtily beat its chest for having way more tannin than the rest of its constituent parts can elegantly support.
All wines will age. Tannins will soften out. Some wines will, no doubt, age better than others. What is important is not the wine's ability to age, it is the wine's ability to evolve into something worth waiting for. Great wines give you something substantially new each time you drink them...some new palette of secondary aromas, the dramatic debut of a heretofore shy mix of flavors, the effortless marriage of fruit, wood, and structure.
Great wines are like great books. No matter how long or short, each time you open them they always have something new to teach.