All science is materialistic

[Angrboda]

You’re response has nothing to do with Clarke’s Third Law. For one thing, he was speaking about technology, not science. For another, he did not say anything about ‘impossible’ (although he used the term in the First and Second Laws).

Thirds and lastly, it’s important to remember that ‘sufficiently advanced’ is a culturally relative term. A cell phone, a handheld torch, or a power saw would certainly seem like magic to a culture that had never experienced them.

Boru

What is technology, but applied science?

If it's applied, that means that it's possible, so your impossibility caveat would not apply even if it were otherwise valid.