Authorship can be weird.
A physicist on a big LHC project will be the author on over 1000 papers after a decade or so (they average around 100 papers a year). In all likelihood they haven't read the vast majority of them, and have contributed directly to around 1% of them.
High energy physicists got sick of bickering over who was on the list and added everyone who had contributed to the experiment infrastructure. There are pros and cons: it's nice to be on all the papers but it's confusing to figure out who did what.