I mean, really, why would it be encrypted?

[ReneZ]

What most people overlook is that the only reason for believung the ms. is a ciphre is the sayso of Voynich. And guys like Friedman fell for it, it is a question of self-assessment. When I, the genius who solved the Purple code is not able to read it it must be something very special.
Just a side remark: I am wondering for a long time if Kircher could read the ms.

I'm sorry, but that is too much of a simplification.

It is not just Voynich's sayso. The majority of modern people think it is a cipher, and this opinion was also fully shared by many of Voynich's contemporaries (Newbold, Manly, Friedman) and later researchers.

While Friedman probably had a high opinion of himself, he also had the capability of self-assessment and humour.
He did try for over 40 years.
When, towards the end, he started the second study group, during the opening speech of the first meeting he said: "others have failed, so why not I".
And at the end he came to the conclusion that it does not look like a cipher.

For what concerns Kircher, he was far from being a genius. He was primarily very busy and very productive, with more imagination than talent.