This is entirely right. The feature as it exists is insane if it doesn't guarantee consistent hashes. However, there are alternatives even in the face of an adv

This is entirely right. The feature as it exists is insane if it doesn't guarantee consistent hashes. However, there are alternatives even in the face of an adversarial GitHub. Every software project could agree on a manifest format and some kind of PKI/WoT to distribute certificates. Pigs would fly first, but it's possible!