"Reliably passing down information" includes a lot of stuff a lot less impressive than "reliably passing down the information required to keep operational a spacecraft mid-flight at the edge of our solar system."
Well the systems controlling Voyager are quite simple, being 1970s technology. Obscure by today's standards perhaps, but not terribly complicated. 70KB of memory, programmed in Fortran and probably some amount of machine or assembly code.
Edit: apparently, due to the post-Apollo budget environment in the 1970s, the Voyager program had to keep costs down so while some new systems were developed, they also reused technology from the Viking program, not even updating or enhancing it.
"The Voyager CCS and Viking CCS would ultimately have the same amount of memory (just under 70kB) despite the routines and programs for Voyager being much more complex. In-flight programming allowed for new routines and programs to be uploaded regularly in non-volatile memory and eliminated the need for large amounts of memory to be required onboard."
I didn't take the GP seriously because of this. Papyrus and clay and stone carvings do not equal operating a network of brittle, bespoke devices across the scale of a solar system. The existence of language, or writing, or even cathedrals or pyramids, do not eclipse this accomplishment. The odds of losing control of a system is proportional to both time and complexity of the system, and the GP ignores the latter factor.
"Reliably" passing down information for future generations is a recent phenomenon. Just go and look at the history of mathematics and there were multiple periods where information was lost and rediscovered.
We are talking past each other, I would not consider a few religions being able to pass down information about that specific religion to future generations as humanity as a whole being able to pass down information reliably. Especially given that the "Vedas" is wholly useless information while things like the Pythagorean theorem were discovered, lost, then rediscovered. We've only recently rediscovered how Romans created concrete?
Also given humanity has existed for many years longer than 4000 years and 4000 years really only represents 160 generations of humans I don't consider that impressive.
We literally have clay tablets from ancient babylon and books that are thoisands of years old. We have traditional crafts like blacksmiths and pottery that were taught for thousands of years.