I think that is understandable, if sad.
I don't think it's sad. It's the way all societies, everywhere, function.
The difficulty comes when somebody doing 'what is right for their family' prevents others that they come into contact with 'doing what is right for their family' - where the understandable priority given to one's own tiny group is actively harmful, rather than passively neutral, to someone else.
But in a world of limited resources, this is always going to be the case. If you push for your child to get a place at a popular school, for example, then someone else's equally deserving child isn't going to get that place. If you accept a job then someone else isn't going to get that job, and perhaps that someone else is objectively much more in need of it than you. If you spend money on things that you LIKE rather than give it to charity, others will suffer so that you can enjoy friviolities.
And so on and so forth. The fact that virtually all of us really only care about ourselves and our families is not new.
Or can we only expect change when the effects of that environmental change are so catastrophically large at an individual family level that they outweigh their pleasure, comfort and enjoyment in the large car?
Realistically, yes.
In fact I've often compared people's attitudes to the environment to the pandemic. People will always tell pollsters that 'more should be done' but in practice they'll rarely be prepared to make significant, let alone ongoing, sacrifices to their own lives. We've seen that so often over the past 19 months. Those chastising others for being 'selfish' for participating in a certain activity - going to the pub, travelling or whatever is today's 'selfish' activity - invariably don't enjoy that activity themselves. So they aren't actually making any sacrifice. They just feel good about feeling morally superior to others.