I feel he was just unusually stupid enough to explicitly put in writing what many academics subtly and implicitly do. People cite their friends, others in the field (with an implicit quid pro quo), etc... even if the research cited has only a tenuous connection to the current paper.

The whole practice of citations is very strange. Many times, I have seen researchers search for works to cite at the time of writing! The top Google result gets cited, without the person having even read the paper before, as all they were looking for was a cite for a pretty generic claim (e.g., machine learning has been applied to health care). I'm not sure that such citations are even bad practice as statements should be evidenced by cites. But as a result, a paper getting cited (e.g., the top ranked Google search for ML and Cancer) doesn't actually mean that the cited paper truly means anything, is credible, or a meaningful scientific contribution.