This is excellent in Bram Büscher's Truth About Nature, that the main response for many environmentalists (and others) to post-truth is:

"Ineffective at best and can lead to a debilitating vicious cycle at worst. This strategy is to spread facts more widely, more vehemently, and more forcefully to their truthfulness (#ClimateTruth!)... [this reinforces] the forces that undermine truths and natures in the first place. "

Totally 100% agreed #Climate