They don’t need friends and family to test deployment. They have a ton of pre-existing test capabilities for that.
I agree they’ll have a short beta, but testing that deployment works shows that deployment works. It doesn’t make any statements regarding the completeness of the client, the finalization of the server etc.
As yet I haven’t seen any in depth feedback from those people running up the client against the Sandbox server to say “All the zones look ready” etc. If someone comes back and says that the 1.12 world and the Classic client are basically identical, I’ll be a lot more confident that that part of the work is done.