I don't get what this is supposed to prove. That my browser doesn't allow websites to declare what encryption they use? I am pretty sure there's a point to all of this, but please let me (and my browser) choose which encryptions I want to trust.
Isn't the idea that the server and client should agree on a common subset? Here, the server's subset is very small, but not esoteric – so then surely it's the client that's lacking in features?
Is this a spec violation or something?