There are countless people with essentially no domain knowledge to speak of after working on the domain for a decade.

I have no idea how the original authors competency is, I know nothing about them.

There is however a strong correlation between people being influencers and kinda mediocre at what they're an influencer in - which is frankly understandable, because a large part of their skillset is usually more towards attracting an audience and making the topic interesting.

Usually the true domain experts rarely interface with the public beyond their professional capacity.