Eh I kind of feel like you can't say that. If something is magical before you learn how it's done, it should be magical after. The magical part isn't "it's actually impossible", but "it's so far from what I could come up on my own", which still holds after you know the secret.
Yes, some excellent magic tricks work even better when you know how they work, especially if they’re the kind that’s based on putting in ridiculous amounts of work or skill/practice.
Penn and Teller play a lot with that idea, for example.
Dani DaOrtiz is one of the best at that. He sells instructions for all his tricks, but he's so good at performing them that they still feel like magic even if you know what he's doing. His appearance on Fool Us¹ is a series of excellent examples of that. He palms a card onto the box, and Teller's reaction when he misses it happening is astonishment because it's such a simple move to spot but done so well Teller missed it despite looking for such moves. That continues as the act goes on, until both Penn & Teller are left experiencing only the joy of the performance & awe at Dani's skill. None of the techniques are ones they don't know about, but Dani does them so well they didn't even try to figure out everything he did, since they knew they'd have to guess what he'd actually done! Penn later described Dani as "the best card magician who has ever lived"².
The best magic tricks tend to be the ones where knowing the secret doesn't ruin the trick, but instead changes it to a show about the skill of the performer. Nobody complains about "spoilers" at a virtuoso's concert, the joy of the performance & the skill of the performer are not ruined by knowing the music beforehand. I think the same can apply to magic, to books, to movies, etc. You can re-read a really good book, or re-watch a really good movie, and the experience won't be ruined by knowing the ending. It'll be different, but not worse. With magic the awe shifts from "how is that possible?" to "how did that person manage to put in the effort to do that so well‽".
I went to a local show of a magician doing the levitating woman where he'd pass the rings across the length of her body to show no strings attached. however, his showmanship was so bad that his assistant was struggling to keep the trick going. when I saw her wince, the secret became very obvious. there she was being very acrobatic suspending her body vertically with just the strength of her one arm, but he took so damn long that she grew tired and her arm strength gave way. she recovered very quickly, but just not quick enough to keep the secret. I felt bad for her as he would more than likely blame her rather than admitting his own bad showmanship and not realizing her effort. It was at that point that I realized just how important the "assistant" really was.
I think I respect Penn and Teller as magicians more since they reveal how some of their tricks work, and yeah the sheer amount of skill required is for some of their tricks is impressive.
I also liked watching The Masked Magician share some behind the scenes of tricks, and even knowing how it's done doesn't make the trick any less impressive.
