Well I can say that your manager friend at Amazon's experience is VERY different from mine. Maybe things have changed in 10 years (its been that long since I worked there).
As for "manager equivalent"- that may be where you come from. In my world, a manager is equal to a normal engineer- they aren't above us. Its simply a different skill set. The only reason they aren't equivalent to a junior is that they must have already worked as an engineer for a few years.
That may be another huge difference- a focus on hierarchy. It seems to be very important to your view of engineering. It isn't to the majority of workplaces. I don't consider it a good thing- I'd rather slit my wrists than deal with the political bullshits that comes with it.
Sounds like you're talking about someone with less than 10 years experience. No one hires me to be faster than a young college hire full of energy, much less faster than the 3 of them you could hire instead of me.
You missed the better part. Besides which- I will absolutely solve any non-trivial problem faster than the 2-3 engineers you can replace me with when you include the time of maintenance and big fixing. Probably by a factor of at least 2. Actually I'll probably do it without including maintenance time, as I'll know how to avoid the problems before running into them (because I probably did so last decade). Of course I'll also be solving problems that they're incapable of at this point in their careers.
You start leading project teams somewhere mid-career, but it's not like it's always the same crew. You're given a project, help work out/negotiate scope/schedule/funding, then deal with all the inevitable panics and hit your date. But half your time is design reviews for other teams, best practices work, that sort of thing - you're generally expected to show that your influence was larger than just your team, come review time. Very different from "a mid-career guy, except I type faster".
Yeah, very different. Dealing with budget, scope, schedule- that's a PMs job. An engineer will have input, but he's not leading that. Especially budget- I've never had to deal with that in my career, and never want to. (I can see why this would be different for other engineering fields where physical components are a major cost. But the most I've ever needed to do was requisition a few hundred dollars worth of software).
Programming is very different. Really most employees change employers every 2-6 years
Sure, but how is that related?
You asked how people were looked at 20 years in. My point is nobody worries about that when you don't hold an employee for more than 4. In fact having more levels would make things harder for a company to hire in experienced workers- if i gets out the new guy Bob got hired in at a higher level, it makes everyone else angry and demoralized. If he's hired in at the same level, no harm done. Especially in smaller companies this is important.
But it doesn't change my original point. You look at it as title inflation. It isn't- its an entirely different way of organizing the workforce. One that focuses less on hierarchy and more on just getting shit done. And a far better one IMO.