There's two points here - parking space and emissions.
Firstly, cars over a certain length should have to straddle (and pay for two parking spaces). In areas where parking is limited, they should not be allowed to park at all. This would mostly apply to cities/towns.
Secondly, emissions/pollution. The solution is to limit who can own a powerful SUV. I would say crofters/farmers/commercial/towing. Nobody else needs one. I live in the Highlands - the roads have huge potholes, we are often snowed in, and off-roading via the ditch can be necessary if there is a stupid tourist blocking the single track road. However, I manage all this in my fiesta (with winter tyres). Most people here do not have SUVs, but ordinary hatchbacks/saloons/estates.
SUVs are not 'needed' for anything except commercial/farming/towing. They may be desired, but they are definitely not necessary. For people who say 'well, it's my choice what to drive', yes it is, but you are affecting others by your choice by being greedy with parking space and polluting our earth.
If you have an electric SUV which fits in a standard UK parking space, I have no issue with your personal choice 