Why would radio signals be all that bothersome? And yes, of course it's easier to build airplanes comparatively, but that doesn't necessarily mean that it's as easy as snapping your fingers. Even in another 100 years, it will likely be easier than it is today (although I'd imagine at some point they will hit a plateau on that), but it still won't be as easy as doing something on a whim. And that's just airplanes, which are a comparatively simple technology. I don't think all technological advancement implies infinite exponential increases. Each will have its limits, and I think that with more complexity will come lower limits.