This is mostly true, except they do store information - it's just not in a consistent, machine readable form.

You can analyze it with specialized tools, and an expert can gain some ability to understand what is stored in a specific link and manually modify it (in a very blunt way)

Scrambling an egg is a good analogy to a point - you can't extract out the training data. It's essentially extremely high, loss full compression from an informational perspective.

You can't get the egg back, but you can modify the model to change the information inside of it. It's extremely complex, but it's a very active field of study - with simpler models we've been able to separate data out from ability - the idea is to use something closer to a database that can be modified without doing brain surgery every time. It's

You can't guarantee destruction of information without complete understanding of the model, but we might be able to scramble personal details... Granted, it's not like we can do now