This is such a tired take. It's part of a steady stream of commentary that reads something like "non-engineering-role X is bullshit." Here, we see engineers reduce the contributions of such common roles as: Product Manger, Program/Project Manager, Scrum Master, Marketer, CEO, etc., as fungible or run by the biggest boogeyman of all, the dreaded MBA. These arguments most typically result from not an inability, but an…
Can they? Certainly. Do they? Well, not as often as you might like.
I used to work for a government contractor who had what I liked to think of as a "butts in seats" strategy. The contractor got paid by taking something like 50% off the top of what the customer paid for the employees (back when I was a contractor in industry, that was more like 15% but that is neither here nor there). The "complexity and nuance" that goes into running that business for a maximal profit involves keeping the direct customers happy---and they're managers, not users---while having as many employees as possible. You need to ride the line between leaving money on the table and having so much broken that higher levels of the customer start to get upset. Laying down narratives is a very important part of that process.
This isn't, however, limited to government contracting. I've ridden quite a few projects into the ground in industry because the goals and incentives of Product Managers, Program Managers, etc., were not aligned with the goal of a successful project simply because there are many ways to be a successful manager and a track record of successful products is not the easiest.
Yes, they were all smart people. Many were even likable, skilled leaders. But if your goal as an engineer is to be part of a successful product and not to be a well-rewarded part of a successful manager's organization, then you will not be happy. Is that what you mean by "professional immaturity"?