Thanks for sharing.
Gave me some things to think about.
We tried moving Sakai (and Apereo? I don't remember) questions over to Stack Exchange in 2014, but the requirements for getting a space were insurmountable for us at the time.
Maybe there are other options? Perhaps using our existing Google group more effectively and/or changing it's settings? I like the idea of getting off email and building more of a knowledge base, but I'm not sure if there are both good solutions that would meet our needs, and whether the community has the energy for such a move.