I think it comes down to a few things-for a period of time he refused to acknowledge that the globe was warming...then he did but said it was not man made (Right now he insists its volcanoes underwater warming the ocean (which I cannot find any scientific support for) This along with his anti vaxx and extremist political posts on twitter have further alienated him (when was the last time you've seen him on a real network? He used to be on several news networks regularly as a guest) He uses an analog approach to forecasting which worked well until we entered a steeper rate of warming 10 yrs ago. Analogs from the 1950's to the 1970's won't do much in today's warmer climate. Thus he has busted horribly especially on temps the last few years. My two cents but agree with your post overall.