I’m not aware of any such policy, I think that simply nobody has tried making one before. I would love to see what you’ve come up with! 😃
P.S. We’ve been looking for someone to make a graphic showing how we’re doing with server donations.
https://originaltrilogy.com/announcement/The-future-of-OT-com-UPDATE-Please-donate/id/64583/page/3#1265319