This is Apple just doing their thing, playing with the equation "Number of Units Shifted * Profit per unit". They've got away with blue murder raising prices, and one suspects there's some overpaid academic somewhere that wanted to try out something "ludicrously priced" just to see what happens. If 33% haven't upgraded, that's still 66% that still HAVE. The equation obviously still balances in their favour, or their balance sheet would be in trouble.
It's been far too long since I've seen desirable Apple hardware, apart from their laptops maybe. OS X; which of course isn't sold as a standalone, if licensed for reasonable amounts (like, say, Win10 Pro pricing - or even a bit higher than that) we'd all snap their arms off to swap. The argument that it would affect Apple's hardware margins to do so doesn't hold so much anymore what with Mac sales generally though the floor (and yes, we still like the laptops!)