I think OP says he would be shocked due to the fact that Bach's wife should have been in the kitchen cleaning up rather than writing music.
seems odd that you think it would be any different because it would be written by a women. what on earth would that have to do with it
In ye old days, I'm willing to take a wild stab and guess that women would not typically have the same schooling and opportunities as men. So yes, I would find it surprising if it had been a woman behind it, because it goes against the grain of society at that time.