That is how Flatpak works right now? If you read the article you can read about two different ways of handling it, runtimes and deduplication. The problem is t

That is how Flatpak works right now? If you read the article you can read about two different ways of handling it, runtimes and deduplication. The problem is the applications have to use the exact same version of a library to get the benefits. With traditional package managers they usually only have 1 version available. With Flatpak you can choose your own version which results in many versions and as such they do not share dependencies. If distros had multiple versions of libraries you would end up with the exact same problem.