older wines should be decanted more carefully
Their flavors change more rapidly AND they need to be transported with more care to avoid unsettling the sediment.
Owen says, "If the wine is an older vintage (10+ years old), I wouldn't put it in a decanter for too long before serving. Maybe just an hour before serving. If it's a very old wine, I'll often just uncork it 20 to 30 minutes before serving and not decant it. (If you're alright with the sediment, this is a safe way to play it). A very old wine can die quickly with too much oxygen, and if you're pulling out a particularly special wine that has spent years slumbering in the cellar, that would be heartbreaking."
Dealing with the sediment is another issue. Owen pointed out that the bottle should be carried the same way it was stored, which means if it was stored on its side, you should carry it home that way to avoid stirring up the bottle—and the same goes for pouring.
Owen also reminded us that, "You'll also need a light source under the neck of the bottle if it's in dark glass to be able to see when the sediment is about to be poured into your glass—and stop pouring just before that happens. It's a complex process, but when it works, it works!"