I agree, the analogy is the only interesting thing about this article. The $315B figure is there just to have a click bait title. He just assumed teachers only

I agree, the analogy is the only interesting thing about this article. The $315B figure is there just to have a click bait title. He just assumed teachers only use 30% of the features from the solutions is used, thus 70% of the money is wasted. But in the real world that's not how it works. The same goes for enterprise market, where feature availability is important. It doesn't mean that every business will use every feature but vendors have developed this multitude of features over the years to address specific needs. It doesn't mean that if you don't use every feature you are throwing money away. You are not expected to use 100% anyway.