This thread sparked a question in my head. Imagine that you are in a situation where you need to dispose of you wallet seed backup, but it is etched on a steel plate - how would you do it? The easiest answer is likely acid, but not everyone has access to it, and depending on the steel plate, it might be even highly resistant to corrosion. Another option is to damage it mechanically - in many of these steel plate products you are supposed to etch the words, so it should be possible to erase them or render unrecognizable. But it's likely hard to do thoroughly and traces of the words could remain.
Any more ideas?
I will bring up the suggestion of using fire to destroy it it one can generate up to the heat temperature required for the sheet to get melted, another perfect means is to go far away, dig the ground and bury it, but erasing them will be a tough task on us because we not not easily achieve doing such, but maybe if there's something called permanent painting or physical destruction if possible depending on the material composition it was made up from.