Nope its because folks are too busy staring at their phones. Frankly, these days a squatch could roller skate through a shopping mall wearing a feather boa and would not be spotted as folks are way to busy typing with their thumbs.
Years ago, one might have been able to argue that a giant ape could possiby roam virtually undetected. Unfortunately , the advent of cell cams has taken away their last best argument...and those fuzzy pictures at 400 yards dont count