I don't think that's true. Lots of global warming sceptics point to some subset of experts who are themselves sceptics. Even subject matter experts have biases. If we ignored those, we'd probably still be unlikely to find many global warming sceptics who had done their own in-depth research. It seems to me that most people in this category (whether it's global warming scepticism, anti-vax, 5G death rays or something else) merely seek to confirm already held beliefs and end up rejecting the opinions of actual experts in favour of misinformation from the kinds of people the blog post is talking about.
Beyond that there are also people with deeper issues than just a disregard for subject matter experts. If you look to extremes (e.g. flat Earth believers), some won't change their mind even when they do the experiments themselves and find proof to the contrary.