I would fear selfies. Our local day hike trail went from 50 people on a Saturday ten years ago to 4,000 people because of social media and people meeting up for selfies. http://www.sfgate.com/outdoors/artic...ot-5755479.php
However, I can drive 3 miles South, pay $6 in parking and hike the same peak on another trail for 6 hours and see a half dozen people.
If selfies at the PCT half way marker become all the rage... be very afraid.