In that case, isn’t an excellent DevOps/sre engineer indistinguishable from an excellent software engineer? Why hold any distinction at all?
It is much more broad than when I was an embedded dev with only one job - to make some driver work on a different architecture.
In almost every reasonably shaped organization the majority of bugs are shipped by developers, not infra/platform/SRE. Localize the pain to the agents who cause it or it will never go away.
A SWE typically won't want to touch infra. That's my experience of course, YMMV.
I have fond memories of the team that worked across three time zones so I would get up to a set of well-described problems that I would solve in the morning (so satisfying), then a nice stretch of feature building after lunch, then a burst of pair coding with my newly arisen colleague, then maybe finishing with writing up any roadblocks or requests for the next person. I got very used to identifying blockers that were out of my area and would be better solved by the domain expert, and also a LOT better at ticket writing. It was a really, really productive and rewarding workflow and one of the key points was not getting bogged down in stuff outside my areas. We also all really appreciated each other because we all experienced each other as magical elves giving answers to hard problems in exchange for answers for easy problems! ;)
Companies hate that. Investing in people who will leave is bad, they think. Put them in their box and let them do what they already know.
Which is why they hire me and call me an SRE. (I don’t use the term. My current title is “principal engineer”. I’m not an engineer, though. Neither are most people here.) And I’m not saying downstack ignorance is great. Profitable for me, sure. But it’s a natural response to companies’ unwillingness to invest in their people. They want them pre-made. Hence the made-up titles for people with breadth.