Agree with you on the problem -> reaction -> solution pattern. It happens. I doubt this is an example though. In the US they have done it over and over again. I don't see them being able to make people leave their phones. If you wanna real uprising take people's phones away. Second, the phone is to valuable to the state. Its their best method of tracking people. They aren't gonna try to keep people from using them.

What they might do is require a "scan" and become more invasive in their searches.

Also, unless this happens in the western country no one will care enough to raise security levels. Its just a fact. If someone tries something like this in the US or Europe then you might see increased restrictions.