From my point in view, encouraging scientists to be socially/politically active is a good thing (what's the alternative?) The problem is the funding process. You don't get money for saying that you don't know.

In my field, a semi-prominent researcher recently published a paper showing that the solar cycle is fundamentally unpredictable. He was ignored, because if it's true, a lot of grant money will just vaporize (the solar cycle destroys satellites every 11 years or so). The same effect is at work in climate science, for sure. Some researchers on solar activity try to claim that the sun is tied to global warming, to get a slice of that pie.

It's all very, very unfortunate, and it's hard to think of a solution. Technologically, it might be wise to register formally all (quantifiable) predictions by an individual, to hold them accountable, and to know whom to trust.