A weak pound. Hmmm. Since the Brexit vote the pound has yo-yo'd a bit but is currently within 10% of it's value to the Euro. So, not a massive discount there to the Europeans who want to import one. The real issue in Euroworld is that the Eurozone itself is not in a great condition to be honest. You have the sloe rise of the "right" in politics in Eastern Europe, Italy, Germany etc and this is having a slow but sure destabilising issue on the Eurozone. however, to really say that any of this is the reason for a small dip in values in VX's where say what 20-30 cars change hands in the UK/Europe a year is codswallop. B@llocks. Nonsense.
Some of the reasons have already been touched on above - some sellers got greedy / over egged the real condition (and therefore value) of their cars, some sellers had previously over-payed and wanted to recoup their losses; less buyers in the market for a near 20 year old car with dwindling parts supply and more potential issues to crop up.
The shift in new cars is to go for finance only, no ownership, options. Just look at the Mercedes and BMW adverts - a few grand down, a few hundred quid a month and a new car every 3 years, some with free insurance and other bits thrown in. It makes for a real compelling argument.
The VX and Elise are not the most comfortable or modern (in terms of comforts) cars. They attract a certain type of owner and in the case of the VX people just do not know about them, what makes them so good, why they should have one UNLESS they know someone who has one or have come across one maybe at a track day or a car meeting.
Also mentioned is the insurance and road tax costs, yes, they are now starting to rise quite a bit and if Jonny and his clams and stuff wasn't around most of these cars would be getting un-insurable as they would be written off with even minor clam damage, just like they were 10 years ago or more!
I do still think good cars will always sell, eventually! mine is now I think a long term keeper. It will morph into a competent track car (I'll never be a competent track driver but will try) that can still be sensibly used on the road. For the money, about £15-17k all in when I have finished (car purchase, Supercharged, harnesses/seats, respray, wheels etc) she'll be a fine toy for me. probably worth around £12k if i decide to sell her, but she'll be bought by someone in the know, not a randomer on Autotrader i believe.