Since arriving at my company, I've come to find that they specifically hire QA Analysts for QA work within sprints across multiple products. I'm aware that this goes against the Scrum Guide which states that within a Scrum Team, there are no sub-teams or hierarchies.
We're continuously hitting the bottleneck every sprint, carrying tickets over, running into the age-old issue of work getting to QA too late in the sprint or coming in all at once, causing the iteration to fail to deliver.
I've attempted to coach my boss on the pitfalls of this approach, discussed the Scrum Guide and had a frank conversation about the repeated failures across all of our products, but the answer to my suggestion that we utilize developer time to do QA tasks, and collectively own the iteration together, was that they have tried to have developers do QA, but they're not skilled enough at QA-type tasks like writing detailed test cases, thinking through all scenarios etc. to be trusted with QA-type work. It had been tried, and quality suffered. So the decision was to have developers develop, and QA do QA.
If your teams do this well, how do you do it?