I would distinguish between "QA as a process" and "QA as a role". We don't know that people in the Quality Assurance role failed; we can observe that the process intended to assure quality did.
I think that's a good distinction. This could be considered a process failure. QA works only if the process allows it to work.
OP here. Agreed. I'll modify my post to clarify that I'm talking about "QA as a process", which usually involves people with "QA as a role", but not always.