> If the crypto is strong, and the key never exfiltrated, then this may be even better than an explicit overwrite, which on some media (like magnetic drives) may still leave trace hints of the old data that advanced techniques could recover.

The idea that magnetic drives left readable traces behind after an overwrite is a myth (especially of modern drives; if I recall the article I'm thinking of correctly the myth may have had a _slim_ chance of being true with old drives [like 100MB days]).