The distances and remoteness mentioned in the article are impressive. And is the human need and ingenuity for communication. It reminded me of William Gibson's description of 1950s farmers in the US using metal wire fences as radio antennas.
In the 70s and 80s (and probably before) in the UK, the BBC used to broadcast occasional "sos messages" [1] prior to the main daily news summaries on FM radio - for people who were away from home and, for whatever reason, uncontactable. They usually related to a relative being dangerously ill. I remember hearing them on my parent's car radio on summer camping trips.
Obviously the uk is a small and quite densely populated island but, without two way personal communications, some needs were similar to those described in the article. It changed a lot of things.
[1] https://swling.com/blog/2012/09/radio-4-and-now-an-urgent-so...
Oh, I remember the equivalent service in National Spanish radio, I think up until the 90s. It was called "Servicio de socorro".
The UK is unevenly populated and it certainly isn't the one island. In Scotland alone, for example, we have had dozens of inhabited islands varying from one or two people up to thousands. We also have places with low population density due to the Highland Clearances (historical ethnic cleansing) and terrain.
I visited a maritime museum which showed a film clip from WW2 about a radio broadcast set up so that merchant sailors could get messages from their family.
I am unable to find an online resource with more info, though I know from general reading and from visiting WW2-era museum ships that sailors were listening to radio shows while at sea. I assume it was all shortwave, back in the time when radio dials included city names.
Honestly I'm very sad that the AM broadcast bands (for those unaware there's two in Europe: long wave and medium wave) have been allowed to fall out of use in the UK without regulatory reform. Fair enough the BBC and commercial broadcasters don't want it any more, Absolute Radio stopped on AM because the fine from Ofcom was actually less than running the transmitter estate for example, but there's no reason community/heritage efforts like Radio Caroline need to be subject to a burdensome licensing regime from an era AM was big business when their band is currently almost dead. In my view we should do the opposite, the whole band should be opened to hobbyist broadcasters for a nominal fee and a power limit of a few hundred watts; it's not like most people have the space to put up an aerial that'll go very far on AM.
It feels very wasteful of a scarce resource to leave this spectrum abandoned, especially when it has interesting properties.