"I think the horse has already left the barn. An individual with $500 worth of equipment could disrupt cellphone reception along an entire corridor of an interstate. What kind of legislation could prevent this? Outlaw private ownership of SDR? I do not think there is any way to stop what is coming..."

Keep in mind that story was just about a single driver's concern over safety. There is also a huge economic incentive for hotels and other business to disrupt signals to force people to pay to use their own wifi services. Marriott tried that. Guess what the consequence was.

So if the horse has already left the barn, how do you explain the fact that cell phone towers seem to work in practice, esp. in large cities like NYC and LA? How is it that nearly every single baseband OS in existence is locked down to comply with FCC regulations?