the voynich manuscript is maddening because statistical analysis proves it's not just gibberish, but it's constructed such that its alphabet isn't remotely sufficient to encode any known language phonetics. like there's just not enough characters to encode an known language.

if you were constructing a hoax in the 1500s voynich is just massive overkill because not only is it too complex to figure out, even the depth of its complexity would not be recognized by a buyer back then so why exert the effort.

this is not my expertise but one possible explanation is the contents are compressed somehow. why and how