However, you also contend that our actual reality is fascinating despite its familiarity: that living with digital technology and science has failed to put a dent in our curiosity about it.

To certain people, I think that's the point you missed. For most people, that statement isn't true - namely, people who aren't fascinated by reality. People who are fascinated by the merely real wouldn't find magic mundane either, even if they grew up in a magical world, because they don't find the familiar mundane. These people are not the normal SF&F reader, though there are certainly a few SF&F fans who fit the description.

The point is that just because it's familiar doesn't mean it must be mundane. However, most people do find the familiar to be mundane, and these same people would find magic mundane as well just as soon as it became familiar.

This is the second time an Eliezer post has reminded me of a certain series of books, where the protagonist is a computer programmer who gets sucked into a world where technology flatly does not work, and in its place is "magic".

In one of the books, the protagonist's sorcerer girlfriend gets transported back to this world, and she is absolutely amazed by such things as microwaves and cell phones and cars and television. This is someone who is used magical teleportation and parchment maps that magically update terrain and scrying pools and such. Yet things we find mundane were incredible to her. Cars in particular scared the bejeezus out of her, and she was used to riding dragons and whatnot.

It's all perspective. If you aren't amazed by science and technology here, then it won't take long before you aren't amazed by magic in a magical world either.

That's the point.