Europas were the first of the 'new generation' homebuilds which applied the principle that you don't have to design your own nuts and bolts if you want to build your own plane.
That and the premise that it would be a modern machine with a good cruise speed and low fuel consumption made them extremely poplular and opened a new niche in the market.
Time has moved on and now there are many more models available which fulfill the dreams of having good speed, low fuel etc but are also quicker and arguable easier to build than a Europa.
Combine that with the, for some challenging, handling and prevalence of the Monowheels in the AAIB reports and you see why they are a lot less popular now.
You only have to look at the amount of Europas for sale (some virtually upon completion) and compare that with RVs and it is clear which one is the more desirable out of the two. And whilst it is not uncommon for folks to build more than one RV I think there are less folks who undertake to build a second Europa.
FD