this would mean it requires a redesign and think for separating user and system package. much like root and rootless containers
Having multiple user accounts is a legit use case - think e.g. a shared device. A typical Linux package manager’s install is a privileged operation. Homebrew on the other hand gives the user that had originally installed it write permissions to certain directories. This strategy enables sudo-less brew install for the specific user and prevent it from being used by anyone else.