...I know that this concept exists, but I've only ever encountered it as a theoretical concept that certain HR departments will pay lip service to, but the reality, in my experience, is different.

For example I have worked in a top-tier investment bank. One year, they had a particularly bad year (because markets were just bad), so while traders in some cases still got bonuses, nobody in the entire Technology Division (since they were seen as being more replaceable) got a bonus. They made up for it by giving everybody a bump in their title (with no bump in pay). That kind of BS is my primary association of what it looks like in practice when people climb the "technical" ladder (rather than the "management" ladder).

In my mind, a carreer progression would have to imply that, as time goes by, your options of things you might do in the organization expand and, since you get to pick and choose from a wider pool, you make choices that are in your best interest meaning more money and more opportunity to influence the direction of the business and all that.

It works that way for management, as the relationships you build with people become an asset that starts paying dividends over time.

For engineering, it works in reverse: Your options become less with time, not more. The determinant of any move you might make within the organization is not so much the opporunity around you doing something new, but the risk around you no longer continuing with what you leave behind. (Or at least that's the way that organizations will mistakenly see it). Say you've built a database that underlies reporting infrastructure that underlies all decision-making in the entire company. Bringing in somebody else to look after the database is a risk that a company usually won't want to take. Ramping up somebody else to learn about the system is a cost they won't want to incur. Congratulations: You're stuck looking after that database for the rest of your time at that organization. That's the reward you get for having done a good job at building that database.

In addition, I would say that over the 10 years that I've been in industry I have seen a cultural change around non-engineering professions moving in on decision-making-territory that would have previously been an engineer's. I'm talking about business managers, designers, product managers, product designers, it infrastructure architects, what have you. 10 years ago, you would have been presented with a problem which, at the face of it, was technical in nature like "build a database and some reporting infrastructure around it". You would have picked a database management system, built the data ingestion infrastructure, created e-mail reports which you designed yourself, etc. etc. Nowadays, you go to person X enterprise IT architect to have them decide which database you can use. You go to a designer to tell you which font to use on the report. You go to a product manager to tell you how often to send the e-mail reports and what the signup-flow should look like, etc. etc. -- Congratulations you have just been reduced to a mere machine executing a business process, not making a single meaningful decision for yourself, and as a result your social standing is barely above that of a machine.