When he says approaches similar to 'other packaging systems', which ones is he referring to? I can see why this is a bad approach but am unfamiliar with what would be considered a better practice (outside of just hosting a .tar on CloudFront).
The main difference is that homebrew actually updates the git tree to provide updated versions of package specs. CocoaPods adds a new directory and some files for each package version, causing the repo to balloon.
No matter which way you slice it, what CocoaPods is doing is a bit daft, especially at their scale.