"CSS pixels haven't reliably corresponded to screen pixels for quite some time now."
Depends what you mean by reliably. I'd say it's a good 90% of the time people aren't zooming or using a mobile browser and they do correspond. And in a world where nearly half of visitors use IE so nothing really works properly anyway, I call that relatively reliable.
I'm just quite depressed by the whole way "retina" has been handled by everyone. There have been many efforts at resolution independence over the last ten years - now when significantly different resolution devices come into the market all that seems to have been thrown out the window and everyone seems to need to go round adding "retina"-specific hacks, "retina"-specific icons and whatnot to everything under the sun.
"We've found ways to avoid almost all problems when zooming Web pages."
As a web developer I look at that statement with eyebrows askew.