How much time and effort may have been put in?

[JoJo_Jost]

Perhaps the most relevant example is the Voynich community itself. Many people set out to research and solve this manuscript, spending hours, days, weeks, months, sometimes years, and sometimes decades putting in 1000s of hours of effort in. Is it so unbelievable that someone may spend an entire year's worth of their free time writing a book meant to be unreadable, just for the sake of it? We tend to assume that if there is meaning in the text then there must have been a use case, but what if the author simply enjoyed writing weird/fancy books?

The problem is probably more that the VMS, at over 200 pages, is so complex and consistent that a rather elaborate generator would have had to be created for it—assuming no language was being encrypted. A language, on the other hand, inherently possesses this consistent complexity. In that respect, only a relatively simple cipher would be necessary.

It is not so much the effort of writing itself, but rather the effort of creating such a complex generator to encrypt “nonsense” that is highly anachronistic.