Now the big issue that's spooking the FAA is that if you go to YouTube and search for FPV you'l find people flying their FPV planes at 2000, 3000 or even 5000ft where they become a risk to full size aircraft - even if they are only 2 or 3lbs of foam I could see them causing some damage to a jet engine. (Alt: but so do birds)
The small subset of idiots who bust the 400ft rule is making the FAA try to ban all FPV or outside line of sight operation which is a terrible idea as there are a lot of practical applications for model aircraft under 400ft (surveying, agriculture, logistics, Search and rescue etc) The FAA should only have jurisdiction over 500ft and in class B airspace as it has been for the past 80 years. They need to get a framework in place for licensed commercial operation under 400ft rather then just trying to ban it outright - people will do it regardless it's better if they are certified and follow some safety rules rather then the under the table hope you don't get caught stuff that's going on now.