It also means we can put an extra layer of QA testing between dev branch and master, which works nicely as a means of forcing communication between devs and QA too, and helps with onboarding (because the product featureset is huge).

Automated tests are great, but having a person read the feature ticket description and testing steps and then check that the functionality actually makes sense before it hits the master branch...

One more tool in the box, and it's a great culture correction mechanism too. Devs who don't test their work before submitting it get it sent back for fixing and feel less productive, so doing things thoroughly the first time feels quicker than rushing it. Doesn't even require management to monitor rates of reopening tickets, etc: people just don't like having to redo things.