The claim that "we get our money from our customers" is, on its face, wrong. Of course we're paid by the company, not the customer. The simple truth this article misses is that your wage is simply the price of your labor, and it is the firm that is paying it. The "value you add for customers" (however that might be measured) really doesn't come into the picture. The job market is competitive, and the amount your company pays you is primarily determined by how much they would have to pay someone else to do the same job.
> the amount your company pays you is primarily determined by how much they would have to pay someone else to do the same job.
This is true, but the thing you're missing is that there's not many folks out there that can add value for customers. That's why engineers who create value get paid so well, which is the articles point.
I've noticed that engineers that get paid the most tend to understand the technical and business trade-offs that come from decisions they make.