I think you missed the mark a bit here. This wasn’t a dependency that was compromised, it was a dep that was malicious from the start. Package manager doesn’t really play into this. Even if this package was vendored the outcome would have been the same.

No, package manager actually DOES play into this. Or, rather, the way best practices it enforces do. I would be seriously surprised if debian shipped malware, because the package manager is configured with debian repos by default and you know you can trust these to have a very strict oversight.

If apt's DNA was to download package binaries straight from Github, then I would blame it on the package manager for making it so inherently easy to download malware, wouldn't I?