Distinguishing Characters

[Koen G]

paradoxically there seems to be so little interest in ciphers from the time of the Voynich manuscript

Correct me if I'm wrong, but so far I am not aware of any cipher that illuminates what could be going on with the VM. I suspect there would be more interest in this if there was a closer connection between the VM and the known ciphers of the time. Right now it feels like looking for a needle in a haystack where you don't even know if there is any needle at all. 

Combing through archives is typically the kind of undertaking that has to be a passion project for the researcher to stay motivated. I think this explains why many people seem not interested: it is the search for ciphers itself that is more rewarding than the relevance for Voynich research so far. It is more like a separate hobby that requires a lot of time and dedication. Of course, studying ciphers in archives might be exactly what will solve the VM one day, but so far the results are discouraging (granted, this could be said about any approach).