For example proper runtime dependency management?

Try updating a single homebrew package to a new major version and watch the other homebrew packages depending on it breaking.

To be fair, that's not a problem unique to homebrew. Gentoo used to break runtime dependencies, too. Although that was a long time ago. Nowadays libs used by other programs are preserved and only deleted when all dependencies have been updated, so breakage no longer occurrs.

For one, it works just fine on multi-user Macs as it installs software under the uid/gid of the user who installed Homebrew somewhere under /usr/local whereas Homebrew installs it the proper way as root:admin and doesn't create a shitload of permission problems.

I can't understand whether you're saying Homebrew does it right or not on multiuser systems.

I have a lot of trouble with Homebrew on multiuser Mac systems. Running `brew install ...` or `brew update` as anyone but the user who originally installed Homebrew almost always fails because of permission errors (or it successfully installs, but then causes permission errors in the future for the user who installed Homebrew). Whenever I need to use Homebrew commands now, I use `sudo -iu otheruser` to switch to the user account who first installed Homebrew in order to avoid the permissions issues. I'm really baffled that Homebrew doesn't support the multiuser system case. Is it so rare to share a system nowadays? I've had this issue on multiple Macs and fresh installs, so I don't think this is some fluke bug.