I'd blame the demand on Europe's higher population density and better public transit - there's not nearly as much "need" (demand?) for vehicles that can make long, sustained trips.
I would blame primarily the higher gasoline price. When gas costs two times more than in US, people suddenly start thinking more whether they really need full size truck to take their groceries.
They're about status. Plenty of people want something small and cheap, and in London EVs don't pay congestion charge, so the incentive is even higher. But that said, if you're an obnoxious commodities trader who just spent £10m on that new place just off the King's Road, you're probably going to buy your wife an X5 to keep the kids safe...
Based on personal observation, most of the big cars you see in much of Europe are also expensive cars, meaning that they're used as a sign of wealth and thus driven by people who don't care so much about gas prices. You see relatively few big, cheap cars, especially compared to the US.
Based on my personal experience, there are a lot of Germans who buy used luxury cars that cannot even afford to fully insure them. They buy either big SUV or sporty Mercedes/ BMW with a big engine that burn gas like crazy just to show off. They also drive it very little and do the bare minimum of service because they cannot afford either. They are also some people who live in very small and cheap apartments just to afford them.
They just have them as a status symbol because they want to feel important/powerful/rich.
That's also one of the richest parts of Germany. Maybe people don't care so much about gas prices when they're driving a company car and make six figures.
Of course there will always be people that can afford/want to have big cars. But it won't change the fact that doubling the gas price will change the behaviour of many people. (Even the tank driving people may have a small second car in the family instead of two tanks)
Public transit replaces short routine trips, which is exactly what those small cars are tailored for.
One big difference is car infrastructure, mostly parking: in many European settlements, from most capitals to the smallest village, an unnecessarily big car is a serious inconvenience. Whereas in the US, even on Manhattan a smaller car won't improve the driving (and parking) experience a lot as everything is built to accommodate big cars, just not in unlimited quantity.
This does not keep most Europeans from theoretically desiring a big car, but it makes not spending on one so much more bearable. The narrow streets use-case makes small cars common enough to make them non-exotic, non-stigmatizing also where streets are wide and parking is one size fits all.
I'd concur, this and more a leaning towards smaller cars, again due to population densities and proximity to resources (shops etc). Which may also explain less pickup trucks, which would be more useful in a more spread out resource/population as would allow large load transportation. Which given distance and time, would make sense. Which equally allows any bulk material resource supplier more able to provide delivery as cost effective for them, again due to population density. After all, if you have a spread out customer base of equal numbers then it may make more sense to not offer delivery, leave that to the customer and offset that with offering cheaper product price. Then any delivery option on offer will be custom and more expensive as would be farmed out, but still an option. So the tendency to go for a pickup truck, increases for the populus in more spread out area's.
But equally can't overlook the government incentives offered in many European countries and those have been IMHO pretty aggressive, making EV's a very tempting option for consumers.
Though, gas/petrol/diesel is more expensive in Europe and does not have the governmental subsidies many other countries offer and is equally very taxed. Again making EV's, very much cost effective for so many. Some places even offer free charging, if not subsidised charging.
So factoring is the demand for smaller vehicles needing to go shorter distances and those incentives/subsidies, then you can see why EV's in Europe garnering much traction.
I almost forgot congestion charges, EV's avoid those and they can add up in some cities/area's (thinking London for example).
American-style pickups in general are unpopular here (in either meaning). For transporting stuff transporter/sprinter-class vehicles are far far more common as well as 3.5 ton transporters, which can have an open cargo area (or an enclosed cargo area) but look totally different from the American style pickup:
