As I've gotten older (currently in my early 30s), my experience has been that most people are resentful and jealous under the surface, and they want to take out that resentment and jealousy on the world in some manner. Particularly in hard-hit and neglected areas of the country where 99% of the motivated and capable people who might have been inclined to help your optimistic vision moved out long ago.
That doesn't mean there's nothing to be done or that every neglected suburb/small town is irredeemable, but I'd be careful not to apply social optimism too generally. No amount of optimism or energy will allow you to grow crops in a salted field, you can only directly help those who want to be helped. Spend your energy where it's most productive.
That said the author is correct in that leading by example, not being a dick about it, and fixing peoples' problems is about the only tool available with any hope of earning the respect of those who disagree with you. So if you have the time, money, skill and energy it's worth at least a few tries before declaring an area beyond repair. :)