The author of the article starts by saying (emphasis mine):
Agile basically solved the problem of how to deliver software. Most any company that applies an agile method and mindset can get working software out the door. Now, the biggest waste in software development seems to be building the wrong product, or the wrong features.
I’m interpreting this as the author saying that we’ve figured out how to efficiently create software with agile, but we are still working out how to effectively deliver it.
Reading over the headline statements on the agile manifesto and focusing on the items on the left you will have an efficient system for developing software. But are they focusing on effectiveness?
Individuals and interactions over processes and toolsWaste reduction by encouraging conversation over heavy process or tools
Working software over comprehensive documentationWaste reduction by building something usable first
Customer collaboration over contract negotiationMore effectiveness focused than the others here, though also the least adhered too
Responding to change over following a planWaste reduction by removing detailed future plans that'll be wrong or unwanted
Seeing three out of four items as efficiency focused is what leads me to think that agile is more about efficiently than effectiveness. The hope is that by being more effiecient you get more time building valuable and effective software, rather than just doing the wrong thing righter. The area of building the right thing is where we should now focus our efforts.