Probably so. They took a lot of heat in the late 1990’s on their first reports, when their alarmist predictions turned out not to be true.
Hence the problem. The activists on this issue are all over the place. The SCIENTISTS are not necessarily all over the place (there are some that are still operating under the notion that a creative exaggeration is helpful to the politics, but not many) but the activists and politicians are still trying to scare people into action. Doesn’t work, historically. It’s not hard to pick out the illogic when they do.
And what do you get from all this “activism”? Shit like Kyoto and Paris, which do virtually nothing to address a very real problem, but allow politicians to sit back and pat themselves on the back believing they have accomplished something.