My friend is very clear as to what they think of gender. They really do see it as “not applicable” to the job they do. This is why they would pick “not applicable” here in this database if they were a musician. I do not see how someone could imply “Not Applicable” would make them someoene human? It seems more logical to read that as “my gender is not applicable to this conversation”.
They certainly do get annoyed at being grouped in with “genderqueer” as they do not identify with the “queer” world. Very much a case of “each to their own definition”. 
I also agree with them. I do not see any reason why people need to be shoved into boxes all the time. Why those people who selected “other” be forced into a box? And whose opinion as to which box they go into? It is hard enough working out release dates of albums
I can just imaging the edit note argument on specifics of gender!
I realise there are some gender campaigners out there who are loud and proud about who they are. There are also others who would rather just get on with life and not become part of some campaign. They just want to live life in their body in their way.
Personally I usually select “Not Applicable” when asked my gender, race, religion. Especially on survey forms. It really is “Not applicable”, but if I found that “other” had then been swapped to “non-binary-genderqueer” I would be very annoyed by that change.
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As to the point about changes during a career. I don’t know why you knock that one back so quickly. It seems quite logical to me that someone can have an early musical career in their “birth gender”, and then later in life they have transitioned to a new gender. But they are still proud of the early career. So this would lead to the need of having a start\end date on the “gender” of their career.
A few people I can point at on UK TV like this - names slip my mind at the moment but there is a historian who regularly appears in these shows whose earlier career was male. She has only slightly adjusted her name and is clearly linked with her previously male past. So for those people who gender is important would want to know when the changes occurred with respect to the career.
MB Database is about data mining. So if you make the data available it will be mined in ways you never expected.
This is a level of complication that MB should not have to deal with. It is rare that the artist is the one uploading or editing data. So how would MB contact the artist to find out how they want to be represented? Just seems a level too far.
What does Wikidata \ Wikimedia do? It seems more logical that this is the kind of data they should be working with. They store much more on artists and their history that MB could ever have space\structure for.
I would not want to see this issue cause the removal of the “gender” option for the artists. I’d just like to see some examples used elsewhere online before trying to convert a Music Database into a gender campaign.
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(ARGH!! I tried to stay away from this thread last time it appeared… I have too many opinions in this one, too many friends deep in this world. Even my ex-partner has a PhD in Gender Studies
I didn’t want to see those kinds of debates appearing here… but now I am dragged in…)