A luxury to a person, might be necessity to another.
As standard of life increases, it has its own effects. Lets take a real life example.
You are having a meeting with a client today at 10 am. He has just landed here by 8am flight and would be returning by 9pm flight. In these 12 hours, he has almost 8 meetings scheduled with different executives, companies and vendors. You exactly have only 1hr or so to pitch your idea to him. Would you risk waiting for the right train or bus, getting smashed and dirty in the thick rush hour crowd in the bus.
You would rather tell your driver to escort you in your cozy air conditioned car, while you finish giving last minute touches to your presentation on the way. You also need not worry, as your wife can use the other car to get to her workplace on time comfortably.
Same is the case with all other 'luxuries'.
To an outsider, they just need to lower their unncesaary greed. But in reality it's all about the standard of living. Unlike the olden days, thanks to the low EMIs and offers, middle class people too can afford a second car.
Regarding the life taken for granted part. I guess every generation says the same; this generation youngsters don't have to face the hardships of our generation, that they aren't frugal enough in their spendings. It's all about standard of living. Would we be ready to live a frugal lifestyle like our elders? Of course not.
That being said, in the case of cities, I completely agree with the author on the parking space part. What's the use of buying cars when you don't have enough parking space!
So let's take luxury out of this picture and think about the after effects of more and more cars getting on the road; traffic, parking and pollution being just a few.
Let's see the world from different perspectives