So if the maintainers haven't done something, we should assume it's upstream's fault for not making it convenient enough for them, or not prompting them enough? For every distro that has packaged their code?
There are real downsides to the maintainer system - it creates a lot of extra, uninteresting work, and frequently no-one's that interested in doing it, especially for smaller packages. That's why there's so much interest in other models.
To give another example, if you install jupyter-notebook through apt on Ubuntu 18.04 today, you get a version with a security issue (CVE-2018-8768) that upstream released a fix for months ago. Package maintainers are not making anyone safer there.