Some of my paints are like 3 years old and they are still totally fine, not dried out at all. I think it's actually good that they are in the metallic tubes because they "hug" the product more, if that makes sense, and allow less air to get inside. Think of it like a toothpaste tube, the ones from plastic expand to their regular size again and let air fill it up, but metallic tubes stay empty when they are empty.

__________________