This is how I read it too. What's more, it looks like they're interested in going senior -> staff; at all Large Tech Companies, senior is a perfectly reasonable "terminal" role for a SWE, and many SWEs don't want to get promoted to staff. (Staff SWE is a different job from senior SWE; you might not want want to do that job, and that's typically fine.)

So I think the lesson here is wrong too - when the manager said

> These tasks aren’t business priorities and had no impact on customers and other teams

that didn't mean they were worthless tasks - just that they weren't business priorities and had no impact on customers or other teams. Which is probably true(ish - I would have phrased it very differently if I were their manager).

Improving the release process is great, and helps the team a ton - and indirectly helps customers by enabling the team to ship faster. This is incredibly valuable! And at the right scale, it can be a staff job: at my Large Tech Company, I know several people that have been promoted to staff SWE for this kind of work, but it's for systems that hundreds of SWEs work on. I also know people that have been promoted to senior SWE for this kind of work - these are systems that tens of SWEs work on. It sounds like this example was more like that - this person was doing a good senior SWE job, and the manager didn't see any reason to course correct given that they had given no signal they wanted to get promoted.

Managers should figure out plans with their employees. It is too easy for someone focused on one thing to get lost in something that doesn't matter. It is your manager job to stop from doing that.

note that often preventing problems is not rewarded. Putting out a fire you caused is. Good managers will help you explain why this not obviously useful thing is valuable because of the proplem it prevented.