Indeed. This seems like a tooling issue, and one that strikes me as more worthy of community attention than reinventing the package manager for the nth time.

Yes, and once we have the tooling to build portable .tar.gz application packages someone should come up with a tool to automatically upgrade them.

Perhaps. Extrapolating the idea that .tar.gz application packages should be standalone, a better system than an external updater might be that the aforementioned build tooling includes an "update" script inside the .tar.gz. Then the user can run them at their own convenience. This is similar to how Firefox's updater works, except Firefox itself does double duty as the update script.

I prefer a binary more willing to interop with the system it’s installed on, rather than the statically linked black boxes we see on end user desktop platforms.