I'm a frustrated developer. I spent most of my career inside very large organizations creating very large, complex software systems with (literally) a cast of thousands. Working on crushingly waterfall projects with a cycle time of 36 months will either suck you dry of the will to develop, or drive you to action. Hence my frustration. It was a fantastic object lesson in what not to do.
Fortunately Bell Labs is full of creative people, and we do experiments. Over time we tried lots of things, keeping the parts that seemed to work well and casting aside the failures. Iterations, shorter-is-better, PRI (hard lesson!), dedicated build machines, small focused teams, collocation, software patterns, org patterns, test driven development, product focus, are some of the things we either derived or adopted before I ever heard of scrum.
Initially a scrum skeptic, once I realized it was a framework that gave consistent names and tons of feedback loops without overly constraining the implementation, I started using it, and it worked well. Only a handful of products I have worked on involved < 10 teams. We brought in Craig many years ago and he was able to show us how to work at our scale effectively. I'm glad it has a name now.
Over the years I have had a chance to be a team member, scrum master and (fake) product owner, so I've seen many sides. It all fits (mostly). Kudos to the original scrum folks for such a tightly knit bit of organizational origami.
I've also worked on a number of projects that were clearly agile that didn't fit any known agile technique. Rare, but really great. An org at 'ri'. :-)
I'm not married to a single scaling solution, and have been cross-trained. I'm more a product of my environment and experiences. For the sort of situations I continue to face, LeSS seems a good fit, and we continue to use it.
My goal is to fix the organization so I can go back to developing. There is nothing more satisfying than being on a high performing team.
Applying Value Stream Mapping is like finding dark matter. You suddenly realize the most massive parts are in the unseen spaces.