Stop asking whether quantum computing is possible

The current SciAm mag has a paywalled article describing three competing research programs trying to build the first quantum computer, and concludes:

The time has come to stop asking whether quantum computing is possible and to start focusing on what it will be able to do. The truth is that we do not know how quantum computing will change the world.

Huhh?

No, quantum computing is probably impossible, and would not change the world even if it were possible.

One supposed application is a "quantum internet", which quantum computers are used as routers to transmit qubits from one user to another. The only known use for that is for so-called quantum cryptography, but that has no advantages over conventional cryptography. It would cost a million times as much, and be hopelessly insecure by today's standards. It cannot authenticate messages, and all implementations have been broken, as far as I know.

The article also mentions quantum clocks. I do not know what that is all about, but we already have extremely cheap clocks that are far more accurate than what is needed by anyone.

Meanwhile, IBM claims to have 5 qubits:

IBM said on Wednesday that it's giving everyone access to one of its quantum computing processors, which can be used to crunch large amounts of data. Anyone can apply through IBM Research's website to test the processor, however, IBM will determine how much access people will have to the processor depending on their technology background -- specifically how knowledgeable they are about quantum technology.

If IBM really had a revolutionary computer, it would be able to figure out something to do with it. No, it cannot "be used to crunch large amounts of data."