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.
I've literally seen this at many dozens of companies, including both "name brand" and startups on the path to acquisition.