Reducing the cars people own would always be the best option. The idea we can mitigate our impact on climate without a major change in lifestyle is farcical. Families/households with two or more cars should be reducing to one car and adapting to meet that change.
My household, with four working adult drivers has one car. I occasionally hire a Cityhop car or van (eg: to load up the boat), but otherwise get by with bike, walking and bus.
Yes, some people have set up their lives around unlimited access to car travel. They need to adapt: live/work/play closer to where they work/live/play