Many interesting weapons were brought home in years past, I have seen examples of many Boer Mausers from the Commonwealth, and all sorts of other weapons, that are now deemed too dangerous for people to own.
After Brexit, maybe you can keep those Martini's- the new EU regs were going to be far more strict than what applies now, apparently.
On a side note, I watch the British Antiques roadshow - years ago, there was an old firearm or other weapon on from time to time- but now, anything of military origin seems to be a incidental piece of gear, or other memorabilia. Have not seen a firearm or sword of any description for a long time.
Is it your sense this is a deliberate effort to reduce interest in arms collecting as a legitimate hobby or enterprise?
I have been reading a bit about the second Afghan war, prompted by a purchase of a very interesting sword at our local gun show- it is a Victorian era Officers sword with an Afghan hilt applied later. The sword was sharpened for field use, yet it shows little signs of battle damage. I think perhaps it was captured from some unfortunate officer and was a war trophy for the Afghan. It is a thought provoking piece of history, I am sure you feel the same way when you handle the Martini. Fascinating to think it could have been used at Kandahar or in the Zulu wars. Someday I may luck into finding out exactly who owned it, there is a seal on it which I cannot identify.