My last job was at a company that designed and built satellites to order. There was a well defined process for this, and systems engineers were a big part of it. Maybe my experience there is distorting my perspective, but it seems to me that any sufficiently complex project needs to include systems engineering, even if the person doing that is not called a systems engineer. Yet as far as I can tell, it isn’t really a thing in the software industry. When I look at job postings and “about us” blog posts about how a company operates, I don’t see systems engineering mentioned. Am I just not seeing it, is it called something else, or is the majority of the industry somehow operating without it?
I’m thinking more of design than oversight. In my experience building a large, complex system without seriously considering the system design (in the way that a systems engineer would) leads to many “oops” moments that will eat into the schedule.