Except that with an open-source tool you have the choice of using it as long as you want. Once it is part of a distribution like Debian or Fedora it is unlikely that it gets removed just because upstream stagnates, and it'll keep running. If there are enough users the distros might even maintain patches of their own, or fork it themselves. See for eg. tinydns, where the original is so old it doesn't even compile, yet there is a working version in Debian.

With closed source you don't have much choice except running an outdated chroot with an old distribution, or stop using it.