No matter their age, cats always play. All it takes is a long piece of fabric dangling or a twist tie on the floor or a laser pointer (or other point of light), and away they go! Suddenly, it’s playtime!
Humans, on the other hand, often forget to play. As we get older it starts to seem frivolous. It becomes something we have to plan or coordinate. If we do it at all. I have a friend who’s favorite question when getting to know people is “what do you do for fun?” It is remarkable how many people can’t even answer that question.