The "AWS ops team" is often 1-2 people and often part of the dev team formally, often augmented by external consultancies like mine. You start seeing that kind of structure in teams with 10+ people when the dev created infra starts collapsing under its own weight and they realise they need people with actual ops skillset.
I have literally never seen this at 20, 400, or 3000 engineers. But the companies that I've worked at have all been "name brand" or startups on the path to acquisition.
