ps4 probably did near 4.5 million in novemebr. 100$ cheaper yea but 4 years older, so 100$ is nothing really, 3ds, GC, and wiiu being cheaper sure didn't make them sell like hot cakes.
You do realise that this is best PS4 year from launch, and $100 price cut during BF deals with some extra deals (like Gamestop gave $50 in store credit) was huge and great deal.
you do realize that ps4 199$ sold out in like a day or 2, they could have well sold over 2 million on Novembe. 3ds was 179.99 in novemebr that only sold like 800k its first yeat i think, its just not about price, it's just a ton of demand for ps4 at that price. just look at xbone, it was 189$ with way more supply, and couldn't beat ps4 despite it launching the X which did great numbers.