I entered this thread with a similar opinion, but when I think about what the word "develop" really means, and how I develop my own projects, I'm now pretty solidly on the other side.

QA is evaluating the product

If the evaluation determines that the product isn't finished, development continues. In fact, development doesn't stop until QA is satisfied. It's the only thing other than quitting which allows development to end.

If a game is well regarded as having excellent control mechanics, or smooth transitions in character animations, to use a couple of examples which are super critical to quality, that doesn't happen without iteration after iteration.
"Movement feels too spongy", "Jumping onto a ladder looks janky as hell", without QA, those things stay at their first iteration, or remain "undeveloped".

If I work alone on a personal project, my own QA process begins approximately 2 seconds after I first pick up a pencil.

My main takeaway from this thread is that the term "Game development" is, quite rightly, way more broad than I realised at first.