It is a totally false that you must age wine...It's a lie.
In fact, throughout the world, most wine is drunk "young" meaning relatively soon after it is produced, perhaps 12 to 18 months; while some wines will "mature" and become better over time, others will not and should be drunk immediately, or within a few years.
In due course all wine goes “over the hill," so even the wines meant to be set aside for many, many years should be drunk before it’s too late.
…remember a famous name on the label is no guarantee whether a wine will age well.
For a wine to age well it needs a good spine…a good backbone! (fruit, tannin, aging in the barrel)
Which means it needs acidity, tannins(time on the grape skin) and aging in oak barrels (of course there are wines that see no oak). Without this structure; flavors will flatten out over time.
Further, while in the bottle I like to say a tug of war ensues that makes the wine go through stages where one factor is overwhelming the other; yet it is perfectly possible that a wine gets expressively mute(where it’s hard to smell or taste anything awe-inspiring or irresistible. They call that a ‘dumb’ wine. Does not mean it’s bad. It’s just not expressive at all. – So be aware of that.
Are older wines better than younger wines? …It’s a matter of taste.
When red wines mature... the bitter tannins will soften and earthy flavors develop, the fruit is less energetic and supple. The wine may remain extremely cerebral and delicious; which is ultimately what you aspire for. Those with the great wine cellars and older classic wines that are well kept. There are wines that are just absolutely incredible when aged!
But there are plenty of people who enjoy buoyant and lively fruit and the tangy acidity of a younger wine. These wines can be just as engaging, nuanced or powerful. It is a matter of preference.
What about the white wines?
White wines are best drunk when young because when they age whites can become honey flavored and nutty.