I'll not argue that encroachment is a problem along the AT. However, most of that will be invisible directly from the trail. As of this writing , the AT is over 99% protected, either by the fact that it crosses public lands or by the corridor itself which is owned and administered by the National Park Service. The trail traverses far fewer roads than ever, and that was a fact that Earl Shaffer drew attention to during and following his '98 hike. He felt that the AT being routed off of the roads a)made the trail more difficult than it was in '48; and b.) some of the community interaction was lost. As a result, the trail as it exists today is protected, albeit by a narrow corridor in some spots. If we don't want to see the cell towers, than we need to quit trying to bring them into the trail experience. According to another thread on this site, technology seems to be a desired addition to a thru hikers gear. people want to be connected, but we don't want to see the evidence. Sorry folks, you can't have it both ways. All of us make the choice as to what kind of trail the AT will become.