I recently read a good Voynich paper that makes me pretty sure that it was an ancient hoax. https://journals.openedition.org/digitalmedievalist/2331 The pages are more linguistically similar when read as flat sheets than when read as bound, and there's illustrations that stretch across the "gutter" between flat sheets that are cut off when looking at the bound manuscript. The manuscript was only bound once, in the fifteenth century (around when the pages have been carbon dated to). This means that whoever bound the manuscript was unable to "read" it, and the pages were likely written sheet by sheet before being bound in an arbitrary order.