Curious if you can expand on your thoughts / experience related to Developers on QA duties, versus a "Developer in Test" designing the frameworks for automation

Curious if you can expand on your thoughts / experience related to Developers on QA duties, versus a "Developer in Test" designing the frameworks for automation (or, would that be company dependant?) The difficulty in recruiting SDET'S / SET's is...ridiculous (though some companies don't different between a strong automation QA and a mid-SDET), however, as a single EG, a top-3 financial firm's Developer in Test positions (agnostic on languages) were the highest paid developers in the company (sans HFT). They were also held to the most strict of hiring standards (target school, Masters, 3.+ GPA, summa cum laude, stable work history of 3-5 years at a time with companies, etc.)