Is it? If you imagine a fixed point in space, a short wave would mean more waves pass through it every second, not less. Short waves have more energy (they have bounce up and down more quickly) which allows them to travel further.
It's true that "shorter" waves would mean higher frequency, but "shortware" radio uses longer (lower-frequency) waves, relative to most other modern radio systems, so it is true that "fewer waves pass through a single point every second".
Also, it is true that for a given amplitude, a higher frequency wave does contain more energy, but typically, higher frequency waves don't travel as far. Shortwave radio travels particularly far because they happen to be in the right frequency to bounce off the ionosphere, which allows them to travel further than line of sight.
Shortwave, as in short with respect to "mediumwave" transmissions, like regular old broadcast AM radio, or "longwave" which can be used to communicate with submerged submarines.
IIRC, subs use ELF or ULF. My understanding is that some of the older subs could trail a long wire antenna behind them.
It'd seem to me that the bandwidth for such would be abysmal.
Is this correct? I did take some EE courses but that was like forty years ago. All I have ever done with that is receive. I should probably learn more.
It's shortwave (1.6MHz - 30MHz) and not "shorter wave". Radio and TV commonly use FM or UHF (300MHz upwards). So the explanation is technically correct: more waves pass a given point in space.
Most of the actual radio transmitters are no longer operated directly by the BBC. As far as I know the only site still under their operation is BBC World Service Atlantic Relay Station on Ascension Island.
Whilst the BBC still produces the radio and TV programme content, in the UK the radio and TV transmitters are operated by Arqiva and World Service shortwave by Babcock.
I was lucky enough to work on one of the last remaining operational high power longwave AM radio transmitters in the UK at Droitwich Transmitting Station. BBC Radio 4 longwave is broadcast at 500kW on 198kHz (locked to a HP 5065 Rubidium standard) and can be received in large parts of western europe.