You are missing the point entirely. This isn't a justification at all, it is an explanation. The article asserts that they can monetize single real names. Some people don't have those, but if Google thinks that they can't monetize that, why should they care?
That is what the article is saying. It didn't miss a thing, it just didn't spell it out in simple english for you.
And for the record, I do not agree with the article that this is the cause of Google's actions.
Look again at the other post from yesterday - the post that talks about how Google realises that there may be a case for not having a single name to rule them all, and that they were looking at way of making the alternative model work, i.e. make money for them.
