Ever try implementing a mirror in a video game? They're just inherently magical objects, portals into an illusory world, you see into them in a way you don't with a picture. A magical talking picture just wouldn't hit the same, it'd be too clearly fictional.

Ever try implementing a mirror in a video game?

Completely off-topic, but how many people would you realistically expect to answer “yes” to that question?

Very few lol, I haven't even tried it myself to be honest but I couldn't quite think of a better way to express what I meant. It's more that if you've ever looked into the kinds of tricks that are necessary to do it, and compare that to how trivial it is to splash a simple texture onto a wall, that's a good demonstration of why they're so much more magical.

Yes. All the things in the mirror are actually there. It’s not just a trick of the light, it’s an actual hole in space leading to a mirror dimension. Kinda creepy if you think about it.