Better than worthwhile.
I know from personal experience that his critique of the environmental movement is correct. It's riddled with know-nothings who've made it "the great cause", their life's work - and with people who care nothing about the environmental issues and a great deal about the political and economic consequences of "environmentally friendly" laws.
But I've never been able to succinctly state the case the way he has.
It's important to note that the criticisms apply equally well to anti-environmentalists - and to pay attention when Crichton says there's a real need to analyze, as best as possible, our effects on the environment.
I am also quite comfortable with his critique of religion and the religious mind-set - keeping in mind that it's a generalization.
Generalizations are indispensible. But why should we put up with fallacies?