Just ask one of these cultists, if they got to be in charge of the globe's thermostat, what temperature they would set it at and why/how they know that is the right temperature, and see what kind of answer you get. If they can't tell you what the ideal temperature is, how can they conclude it's getting too hot or too cold? If they can tell you what the ideal temperature is, getting them to reveal the source of their esoteric and arcane knowledge is usually worth a pretty good laugh.
In their theory the Arctic is warming the most and warming the most in winter. Looking at the data, that appears to be true. That means less severe Arctic outbreaks, less severe winters here. The usual answer I get is that we need severe winters to kill off mosquitoes or something like that. But malaria and yellow fever and other mosquito-born diseases used to be endemic here up to the Arctic. They were tempered by severe winters but came back every spring. The bottom line is we don't need severe winters to eliminate mosquito-born diseases, we have much better methods mostly related to economic progress and decent border health screening.
Finally I ask what the actual damage is. There is nothing they can point to except allegedly worse weather. The problem is that it is not worse. We have yet to repeat the dust bowl temperatures or conditions here in the US. Then they point to sea level rise. But that's an inch per decade which matches up with previous natural rises. That rate will fall again as it always has, naturally.