I dont drive a SUV.
However, everyone I know who does who talks about 'needing' one, it's not about living up a track, but the number of seats.
The problem isnt the big cars, it's that a standard 5 seater is really a 4 seater these days due to children's car seats being over 1 standard seat width.
Many families have more than 2 children, particularly these days with blended families being more common, and while you might not need to transport 5 people every day on the school run, if you want to make your DSC feel part of the family, things like being able to all travel in the car together matter.
Many families have elderly relatives who live with them or regularly need to be transported - meaning they need that extra seat space.
I'm not sure if children's high back boosters and car seats really do need to be as wide as they are, getting cars back so you can transport 3 children who all need high back boosters in the back or 2 children and 1 adult (who's not a small size 6), would do wonders for reducing the demand for larger cars.
It seems easier to tackle the car seat issue than the car size issue at this point. Much easier to find a way for small cars to work for a range of families than just make people buy 2 small cars because they can't get 1 big one that fits everyone in.