Most people think pouring wine in a decanter is an act reserved for venerable old bottles that have shed sediment and thus need to be decanted to leave those solids in the bottle. You can also use it on young wines of any style or color, if you so choose.
A sommelier friend of mine once compared wine coming out of a bottle to a winter jacket you pull out of a cedar closet after months of storage: you need to give it some air so it stops smelling like the closet. In the same way, pouring a younger bottle into a decanter can give it some welcome aeration and help the aromas open up. It is true for tannic young reds, but also for a light white that is feeling a little timid on the nose.
In the cases of young wines or white wines, you’re not removing sediment, so the process is called carafing, rather than decanting (which implies leaving heavier stuff at the bottom). You can do it more rapidly – in fact, the more vigorously you do it, the more oxygen is brought in to aerate the wines.
It’s always a question of taste, of course. But if a wine seems closed or inexpressive, think about it. It might just need some fresh air.