There is some evidence that women scientists are being selectively excluded from Wikipedia. As one researcher put it, ‘Women academics are twice as likely to be nominated for deletion as you would expect from the proportion of women among Wikipedia biographies.’

Some sources: https://www.chemistryworld.com/news/female-scientists-pages-... https://www.nature.com/articles/d41586-018-05947-8

That doesn't directly explain why the articles that are there would be so shy on information, but it does suggest that people won't spend a lot of work on a topic for which deletion may occur, discouraging people from making improvements.