From the BBC:
If written by disarmed British subjects (and they are subjects if they’re disarmed), maybe they don’t understand the 10mm. Of course, they could’ve just looked up the Wikipedia page for the 10mm and read the first few lines:
Although it was selected by the Federal Bureau of Investigation for use in the field following the 1986 F.B.I. Miami Shootout, their Firearms Training Unit “concluded that its recoil was excessive in terms of training for average agent/police officer competency of use and qualification“, and the pistols that chambered it were too large for some small-handed individuals. These issues led to the creation and eventual adoption of a shorter version of the 10mm that would evolve into what is today the .40 S&W.
The FBI wanted a new gun after the Miami Shootout, which showed them that 9mm had not performed well. There were other lessons to learn from the Miami Shootout, but they did reason that more power was needed and the 9mm of the day wasn’t cutting it.
The solution of the 10mm ended up going too far, too fast. There is no “relatively light and easy to shoot” to a 10mm, unless it’s ported and vented and comped and tweaked. The 10mm is a stout round, and a good round, but it’s not “light and easy to shoot”. Considering the other two guns on their list were a Sig 9mm and an AR-15, both of which are actually light and easy to shoot, it makes even less sense.
But the media, after all, are clueless.