Hey, that's an interesting question, BBR. I'm an old fart on this forum and I can say that it's better for me, even though I voted that age was just a number.
I have always believed that "age" is a relative thing. For instance, maturity is not a function of age - I think some seventeen-year-olds are more mature than some forty-year-olds. Getting older does not necessarily make you wiser or more adult. As for aging... personally, I'm in better physical condition now at fifty than I was at seventeen.
Something that makes tickling better with age is my own attitude about it. I'm a lot less shy about tickling now than I was in my youth. When I was young, if I witnessed someone tickling someone else I'd blush bright red and haul-ass out of the area for fear that someone would see my interest. Now I'm more likely to help.