Hash essentially proves that the file you downloaded is the same as the file that was uploaded. It tells you nothing about Who uploaded the file. An attacker co

Hash essentially proves that the file you downloaded is the same as the file that was uploaded. It tells you nothing about Who uploaded the file. An attacker could make you download their own file, but then the hash of the file won't match what's published (unless the attacker changes the published hash). A GPG sig proves that the file was signed & uploaded by the author, which defacto doubles as proof that it's the same file. The idea here is that the author uploads their public key, signs the package with their private key, and now there's an association between the package and the author. An attacker would have to obtain the author's private key, or replace the public key with their own. Changing the public key, however, is a big red flag.