The Voynich Manuscript is a cipher because...?

[ReneZ]

De rhein een cepain faals mayneli oen the pelain.

In fact, this type of alternative and inconsistent spelling (though maybe not quite as adventurous) should probably be expected.
I wouldn't call it part of a cipher....

When I occasionally try to read German texts from 15th-16th Century books and MSs, they come across as something like the above, compared to modern German.