It increases complexity at every level from the apple developer, to the third party developer, to the end user. The costs aren't even manageable without additio

It increases complexity at every level from the apple developer, to the third party developer, to the end user. The costs aren't even manageable without additional restrictions. Red Hat only back-ports packages because they are paid to do so per their support contracts. And even under RHEL, you may have to upgrade to the latest packages (for your OS version) to receive support. And anyway, if you don't trust your OS vendor to not try to screw you over (planned obsolescence) in major releases, why would you trust them for any update whatsoever? Lack of vendor trust is not something you solve through packaging.