I wonder how much your first point might be due to the view getting excited about fountain of youth type things is a bit of a taboo, too vain and semi sinful. But if you look at behavior its a bit different. Several multi-billion dollar industries about looking and feeling young. But few are really ready to discuss that with just anyone they meet.
In some cases the model is for delivering the results is all about doing so gradually so its not quite as noticeable to those one interacts with on a daily/frequent basis.