You're not alone, wikipedia for zip says
> ZIP supports a simple password-based symmetric encryption system generally known as ZipCrypto. It is documented in the ZIP specification, and known to be seriously flawed. In particular, it is vulnerable to known-plaintext attacks, which are in some cases made worse by poor implementations of random-number generators. https://en.wikipedia.org/wiki/Zip_(file_format)#Encryption
IMO the fact that the author was able to recover the password at all indicates weakness. Something encrypted with AES-GCM would presumably be all but impossible.
Wonder if he tried hashcat first: https://hashcat.net/hashcat/
We won’t really know the true value of bitcoin until options are widely available on retail exchanges like fidelity or at least tdameritrade using people’s normal brokerage and ira accounts.
Well, it looks like it's a lot harder than I thought. You still need the right software and hardware but you also need the right person to do it.
Most of what I read was above my understanding but it was good reading anyhow. Good job on the recovery and good job writing about it.