If you want to be an authoritarian ruler, truth is the first thing you have to eliminate! If noone knows what is true, a leader can tell you what to believe! Science is our method to determine truth! A führer cannot have that!

More than that if you're a professor (and thus an educator for the next generation) you're now incentivized to modify your speech in favour of the authoritarian in order to keep getting funding.

I wouldn't underestimate the degree to which funding to these is being cut because climate scientists have historically been politically opposed to certain large republican donors that make their fortunes burning fossil fuels.

It was also the first things Hitler and Mussolini did once they got power.