The trend I see is described by Putt's Law:
https://en.wikipedia.org/wiki/Putt%27s_Law_and_the_Successful_TechnocratTechnology is dominated by two types of people, those who understand what they do not manage and those who manage what they do not understand.
Back in the old days, senior managers in an engineering company were former engineers, and often very good ones. If needed, they could go to the lab and actually do real work and teach younger staff. The problem with those guys is that they were not trained business managers, and often had little idea of finance. At one company, they had these engineering trained managers, but
they literally didn't know the cost of the products they were making. That was something for finance to "sort out". To stay in business you gotta know margins, ROI and all that other stuff. That is before "optimising shareholder returns".
So what happened is that senior managers were recruited from business trained managers, who were on top of the finance from day 1. Unfortunately, these guys and gals know f*** all about engineering. As the old engineer-turned-managers retire, that leaves the engineers with no one to guide them, and no one to back up their decisions (aka "top cover"). Almost no one above had an engineering background, all the way up to the CEO.
As we know, engineering is about details, but all the managers want to do now is reduce time and cost, regardless. They are completely unable to offer any advice about what a good solution should be, nor how to achieve it. They will always pick what has the lowest immediate time/cost. They reject anything that exceeds time/cost, until you propose a solution that cuts all the corners and has a high risk.
Old IP is milked for far longer than it should, and the current generation of engineers struggles to maintain it, let alone generate a new design. All the knowledge has been lost as engineers are moved around and/or retire.
I've also found that management are quite unable to diagnose poor management structure, or improve it. All they can think of is moving a project manager sideways, and pulling in someone new. You end up with a revolving door of managers, multiple managers fighting over the same people, new managers who know less about the project than the last one.
Once the spiral of decline sets in, it seems unstoppable. Profitability continues to reduce until the business collapses or is sold off.
The pattern at Boeing is exactly the same I've seen at other large engineering companies which trade on reputation and some good legacy products. It might take a decade or two, but you end up with Putts Laws. The engineers who know their stuff are routinely overruled by management, even though the managers don't have the knowledge to make a proper decision.