Okay yeah that makes sense. So that rules out founding cults that use the information as their holy book. But it could allow for "keep it secret, keep it safe" cults where there's a holy object that they know is important but don't know contains the data. (But it can't be SO interesting that people try to inspect and understand it and inadvertently discover the data).
I wonder if you could rely on your buddy in the future knowing what your favorite password is and encrypting the data somehow.
Does it need to be discovered ASAP in that 20 year gap or can it be later on in that period once they know that you specifically are selected for the mission?
You've just opened a wikipedia rabbit hole. Wish me luck I may never return.