Have a listen - from 5:12 to 8:50.
Piper says that a community with a 'strong masculine feel' creates a space that is big and roomy and has space in it for many feminine feels. A man who is prominently masculine can also be appropriately feminine. A woman who is prominently feminine, can also be appropriately masculine. He defines what he means by masculine and feminine.
Masculine = having backbone, being articulate and thoughtful
Feminine = being tender, kind, nurturing, warm, artistic, liking to write.
Trying to work it out... The overall vibe of Christianity (by which I think he means the Christian community) is to be masculine - tough, backbone, powerful, authoritative. "Strong singing primarily led by men, and then a voice from God is heard."
So it's not just about having men in leadership roles, it is about those more 'manly' qualities being on display. It wouldn't be right for an artsy guy to be leading a church in an artsy way. He might be being inappropriately feminine. But maybe if he were to do that more in the background, in an overall context of 'manliness', it would be okay. Is that it?
Piper is winsome and eloquent and I have sympathy for what he is saying, but I don't think his categories of masculinity and femininity are biblical. Am I wrong? Point me to verses.
Piper is advocating more than just that men should occupy leadership roles in church. He may not be after a culture where all men play football, but I think he is saying that that the stereotypical man vibe is to dominate our experience of Christianity.