The article is about how futile most people's efforts are at helping the environment. And though it's a caricature, the article is, in essence, mostly correct.
What's that? It's not really helping the environment much to compost? Damn right it's not. I mean, it makes a bit of difference. A bit. But not much. It's better than voting, which makes, in terms of elections anyway, no difference. But that's a rant for another day.
It's not that I believe people should not strive to make the world a better place. Indeed, it's the guiding principle of my whole life (see http://jimdavies.blogspot.com/2005/01/meaning-of-life-nutshell-version.html)
It's that if you look at the things you spend your time doing, there is great variation in how much good those things do. And if you're working for a better world, you should be maximizing your positive effect. Try to win a few victories for humanity before you die.
You might be thinking that all we can do is our little part. Well, for many people, that's true. But others have a chance to make large-scale positive changes to our world. Politicians and scientists come to mind. It only took one person to discover antibiotics, or that washing your hands saves women's lives in childbirth, or the world-wide web. If you have a chance to make a change of this nature, with such incredible ramifications, then what are you doing wasting your time sorting your recycling bin?
What I don't like is any complacency as a result of doing a bunch of little things, if it keeps you from striving for doing something earth-changingly great. So please don't feel smug and satisfied about the tiny things you do to help the environment or social welfare, unless little things are all you are capable of. And if you have not tried to make large scale changes, you really don't know, do you?