Because they would likely have a higher hurdle for being convinced that we may indeed need to sacrifice economic growth to change the course of humanity's futur

Because they would likely have a higher hurdle for being convinced that we may indeed need to sacrifice economic growth to change the course of humanity's future for the better. If they do their research and are convinced, it would mean a lot more to me than if someone who supported the conclusions of environmentalists' apriori reaches the same conclusion. If there is any such bias among climate scientists (e.g. people that go into climate science already hold certain beliefs about what should be done politically, and inadvertently favour the models / parameters / methodology that support their beliefs), this would help mitigate it to some extent.