I agree with much of this post, but particularly this paragraph. I was going to add something like this to my original post in this thread, but you've done it for me and better than I could've said it lol.
That's sort of how I see Nadal too, and why I'd like the young version back. I can't get the young Nadal pirate pants look out of my head, and the contrast he created with Federer at the height of the rivalry was so cool. Today, he's still Rafa, but he's not really unique in style. Tennis style yes, but not the overall look. Now he's just an old (still great) tennis player. To me at least.
And like you said, it's not just Nadal. I have a couple childhood friends that I don't talk to anymore or very rarely, and we've all gotten a bit fatter, but I still see them as teenagers at the rare times we do talk, and luckily they haven't changed at all personality wise.