I'm not one to appeal to authority but "author should take a course" is akin to ad hominem when a quick look at their profile (https://www.practicalreporting.com/about-nick-desbarats - https://www.linkedin.com/in/nickdesbarats/) tells you that he's been doing dataviz and statistics for a long time.
I'm not one to appeal to authority either which is why I am making objective arguments about what is presented.
And yes he should go on a stats course. I dread to think the chaos he’s spread to people who don’t know better.
Ad hominem arguments, however, should also be ignored. Saying that I'm unqualified doesn't prove anything and adds nothing to the discussion.
If you have specific criticisms of my reasoning, I'm more than happy to listen. If all you have are personal insults, however, well, enjoy the rest of your day.