If you want the perfect example of that problem, look to Windows.

A couple of years back Microsoft discovered some kind of issue with their redistributable dlls.

They patched Office etc, but could only offer a scanner that would check each and every dll to see if it was of a vulnerable version. And asked users to pester third party software providers for updates if the scanner found any.

I wouldn't move from a package system to an "everything has to be statically compiled" system. But it would be a nice option to have when most of the software in your distro it's ok but you want to run some app without upgrading your whole distro/OS.

In the same way as you upgrade library you can just upgrade your software...