> For global rankings you don't need to know that user 1456 has rank 56, you just need to know that somebody holds that rank.
Isn't the purpose of global rankings to know how any given user is ranked globally? It's not much of a ranking system if all you can say is, "Yes, we have one million users, and they are ranked 1 to 1,000,000. We are not able to identify who is what rank."
What's wrong with "we have one million users. You are ranked 45698th. The one below you is proplaya92, the one above you chose to have his name redacted" (but we can tell you his playtime on all characters, his k/d ratio, etc).
Isn't the purpose of global rankings to know how any given user is ranked globally? It's not much of a ranking system if all you can say is, "Yes, we have one million users, and they are ranked 1 to 1,000,000. We are not able to identify who is what rank."