Why does Blizzard use SMS authentication without a security order?

Because of the delay, there is no updated version.

Because of delay or no update, the one-click login function of Battle.net client of mobile phone is temporarily unavailable.

A security token is a small hardware device that its owner carries to allow access to network services. The device can be in the form of a smart card or embedded in a common object such as a key chain. Security tokens provide additional assurance through two authentication methods: the user has a personal identification number that identifies the user as the owner of a specific device, and then the device displays a number that uniquely identifies the user to the device and allows them to log in. Each user's security token changes frequently, usually about five minutes.