You can't blame distribution maintainers for not wanting to expose their users to a constant stream of the newest exciting quirky features the authors have decided to cram into the current release just to be able to keep on top of all of the bugfixes. New releases all also tend to implicitly have new or different sets of dependencies, and distributors have a duty to make sure these various dependencies that exist in their distribution can coexist and interoperate
Authors declaring whatever versions they no longer care about as "unsupported" is a rather unhelpful trait that ignores where their users are (distributions) and what a lot of their users actually want (stability).
I'm sure developers would ideally like to have users suckling at the teat of their latest tagged changeset and perpetually excited about the latest enhancements in each and every release. But really I'd wager that most people, of the ~20-30 applications and desktop components they use every day, by and large... they'd just like most of them to behave like they did yesterday - or last week - or last month - as long as it's reliable.