One solution would be requiring special license for larger vehicles.
A lot of people claim they need a car to get around. A normal license should allow you to drive just that - a sub 1 tonne vehicle.
Now, if you fancy a large utility vehicle with lots of blind zones and taking up extra space - that's no problem, just get extra training to learn how to drive it safely and get reevaluated yearly to show that you are not a danger on the road. A lower threshold to losing or suspending your license would help too.
This would dissuade a lot of people from upgrading to a large vehicles.