I know nothing about the musicians they have invited or considered inviting but I would think the controversy is purely because the person is not a fur themselves. A furry convention is an event where people from the fandom get together. Bringing in an outsider is not serving that role, particularly when there are people in the fandom who could do the same thing.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
I know nothing about the musicians they have invited or considered inviting but I would think the controversy is purely because the person is not a fur themselves. A furry convention is an event where people from the fandom get together. Bringing in an outsider is not serving that role, particularly when there are people in the fandom who could do the same thing.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~