> It does, but you loose some of the features people take for granted.
Excuse me, but so what? This is not a "taken for granted" usage of the protocol.
> I seriously wonder how this could spread, after all you don't just have a large Ethernet domain in your international company.
Oh, my dear lord. I'm assuming you've never worked in a large environment. _Of course_ they have a single large or several large domains (in the Microsoft Active Directory sense) for unified email authenticatoin, and potentially for payroll management and corporate ID's. While the particular systems may be somewhat independent, they are _inevitably_ chained together by various poorly secured portals and gateways in a large environment.
If instead you meant "you don't have a large Ethernet domain", again, you clearly haven't dealt with the kind of large environment I have, where the admins leave things open "because we're not a target" or because "if they're inside our network, we're doomed anyway".
> SMB is one of the first things to go.
I'm afraid it's built into every Windows machine. Go looking around for the hidden "C$" share on every windows box, which is critical to the use of "Powershell" for systems administration. Unless you've been extremely cautious about firewalling things in your core switches and quite strict about treating all individual Windows systems as potentially hostile, it's enabled on all of them.