One superficial guess is that comes to mind immediately is that research got easier for authors with search engines compared to the intensive old library archiv

One superficial guess is that comes to mind immediately is that research got easier for authors with search engines compared to the intensive old library archives primary sources involved before. It would lower the barrier but wouldn't account for motivation. In The Name of the Rose was a difficult read that called for a guide book but it gave a great sense of "we have been here before" in "echoes" of precursors like heresies which were largely separated from the Protestant Reformation's success from lack of backing and Dulcinians who essentially were eerily similiar to Communists before Marx but without the benefit of rifles to surplant knights and lacked the athiesm of course.