I built products at Stripe as an engineer and never worked with an explicit QA team. Each team was responsible for the quality to a large extent.
That being said, QA is definitely an important aspect of software development - regardless of who owns this work. Imo, instead of having a QA engineer per team or a few teams, you should have a QA shape role (similar to AVE you mentioned) that oversees a large area like an Org and pushes hard to make sure quality standards are held high across teams.
It's also trivial for engineers these days to have great e2e automated test coverage with AI. We're actually building getlark.ai that helps engineers with this.
The idea that test coverage equates to well-tested software is one of the unfortunate consequences of MBAs killing QA departments.
https://news.ycombinator.com/item?id=47503348
damn I'm legit not AI bro I think we're all just getting too skeptical these days. Just wanted to express my viewpoint and I mentioned what we're building because it seemed relevant, this isn't a sales motivated post.