As a sort of incidental observation, I would say there were a lot of foreign tourists doing the JMT. I don't know if this is something new, but it was quite a contrast from all the other places I go backpacking. I guess all these "Best of" lists placing it up there with Annapurna, etc has put it on the bucket list of people who otherwise might not come here.
Actually, it was kind of fun meeting people from all over (including elsewhere in the US), but I also suspect a lot of these people (including Americans) are probably inexperienced backpackers without a well-informed knowledge of backcountry practices. I have done several of the well-known backpacking trips in South America, and there is the major problem of having inexperienced people from all over the world coming to do their first backpacking trips and doing some really piggy things, showing no respect for nature. Fortunately, it is nowhere nearly as bad here, probably because our Park Service does a better job of educating newby backpackers. But I wish the responsible agencies would oversee the JMT a little better. I was horribly appalled to see a group of young male (US) bozos camping on a fragile meadow at Guitar Lake (elevation 11,500') I can easily see how the JMT corridor could become a sort of national sacrifice zone