I'd wholeheartedly agree with your critique if the text was published as a tweet storm.
The thing is, this isn't news reporting at all. It's a popsci writeup of the history of the immune system, the history of the discovery of the immune system and a glimpse into its complexity that uses Covid news as the textual equivalent of a cover image. If you have a print of 20000 Leagues under the Sea and the cover shows the kraken attack, would you complain about the number of chapters that don't contain a kraken at all?
The thing is, this isn't news reporting at all. It's a popsci writeup of the history of the immune system, the history of the discovery of the immune system and a glimpse into its complexity that uses Covid news as the textual equivalent of a cover image. If you have a print of 20000 Leagues under the Sea and the cover shows the kraken attack, would you complain about the number of chapters that don't contain a kraken at all?