The % of UK PPLs with a current UK/JAA IR is way below 5%, nearer to 1% if anything. From those I've met it's clear most of them are "old" cases who did it under the old 700-hr concession, etc.
The USA is a much better environment for IFR than Europe. They have lots of hard runways and lots of instrument approaches. Over here, one can fly IFR between large airports OK, and the rest of the time it's "DIY letdown time" which understandably a lot of people don't want to do, especially if flying for a purpose e.g. visiting a customer. So, the USA has a lot more instrument pilots.
The USA also has a lot more money sloshing around the GA community. Apart from a small group of IFR owner-pilots, probably under 1000 total, most of European certified GA exists on really minimal budgets. Just look around the local airfield. This is reflected strongly in the writing and the products advertised.
Why doesn't a Garmin 396 work over here, SF?
The account of a refusal of an offered story is something I've come across myself. I am no judge of own material but was strongly encouraged by others to write in. The mags all wrote back saying they are inundated with material and so can pick and choose. Yet a lot of the content remains poor.