The problem with this approach is similar to the problem of having a dedicated org for ops: the qa/testing org is disjointed from any sense of delivering business value and its goals are somewhat arbitrary. This team usually does not have a good understanding of what devs workflow looks like and instead it mandates some things that look good on paper but end up being quite useless in practice. Eg “have functional tests for every application” becomes a mandate that devs pay lip service to. It becomes another annoying box that devs need to check rather than something that actually improves the reliability of their applications.

A better approach is to discuss the reliability goals with the dev team and let them employ/buy any testing tools they need and hold the team responsible for the result. Developers want to build reliable apps. They know how their applications work. They want what they build to not break.