Interesting to read about the (literal) bandwidth limitations on data rates. It's something I've been aware of but not fully understood for a long time. "Why can't you just turn the wave on and off faster", etc...
Instead of talking about the fundamentals like Fourier transforms, Shannon/Nyquist and wave propagation i usually refer to human speech: how increasing the rate of speech (signalling rate) comes with 1) substantial reduction in transmitting distance as the environment affects signal quality and 2) places a higher burden on error correction (interpretation of language) that is independent of the actual ability for the transmitter to create the faster speech.
