By that definition, almost no software in Debian could be called "stable", as most software has at least one known bug.
When people talk about "stableness" and distributions, we're usually referring to the stableness of interfaces offered by the distribution together with the package.
> There's really no reason at all to use such an old version
Sometimes though, there is. And for those people, they can use the distribution they wish. If you want to get the latest versions via a package repository, use a package repository that fits with what you want.
But you cannot dictate what others need or want. That's why there is a choice in the first place.
