Server structure and netcode can be changed and modified. They're not set in stone.
That would be changes like now from 1-0 -> 2.0 thats now something you can just do in a few weeks. I doubt such a massive change would be an option since it cost a shitload of money and time for something that is maybe not even wanted. And it would cause other problems, ppl would just jump to other servers to ninja stuff and go back to their own after it. It would make market pricing way more difficult if you would need to check every server each time and so on.

And I don't really understand why, this is kinda the opposite of what they do with regional servers so its more then unrealistic. If you wan't to play together with your friends just choose the same server.