When you can’t get what you want, you teach yourself to want what you can get and then preach to everyone else that they should want it too. This applies to many other things too beyond just cars.
It’s not that the criticism of private cars isn’t valid, but not having one because you can’t afford it isn’t virtuous. It’s only virtuous when you could easily have one but choose not to.
I think a lot of people are annoyed by car centrism. It’s not that they want a car, it’s that so many people having cars prevents them from having cheap trains / trams, bicycle lanes, mixed zoning, multi-layers multipurpose buildings, etc. Cars undermine a lot of other forms of transport and enable a more atomized culture that many people dislike.
I use public transport exclusively and I’m not annoyed with the cars. It’s just that life is complicated and cars are necessity for many people for plethora of reasons.