The public suffers anytime knowledge is lost.
As we lose the information, we lose context, and without context 'facts' about the past begin to lose meaning to the present reader.
History, and the stories we have, is/are mankind's most important asset. Without the context of our past as a species, we lose the ability to navigate into the future effectively (without crossing into unfortunate places again, like world war, or slavery, etc.).
We have nothing but stories. Without those, we are nothing.
500 years from now we're going to be faced with a totally different problem - if a user wants to learn about the year 2018 where do they start? Official documents will appear to be stored beside the thoughts of Kardashians besides trolls. It'll be very hard to parse through any information to get an actual sense of what was happening.
I mean, it's the same problem, using the primary sources to try and figure out the truth, but it'll be the opposite problem as we have now.
That's true, but on a timeline of human history that's a pretty brief window and there was a lot of distrust in the medium at that time. We're going to have ~30 years where they have to rely on the old methodologies still, but the 20th century is a whole new ball game. They won't be able to retrieve circa 2000 floppy disks, no, but I feel like a lot of what's been around for the last decade is going to probably stick around.
That being said, on a timescale as long as 5 centuries, I don't think anyone can even begin to fathom in the slightest with any degree of confidence what anything will be like. I just hope the advances this century might make it a possibility I can exist long enough to see it myself.
You dont even need to talk in 5 centuries. 5 decades themselves should be sufficient to be unpredictable.
The fact that we cant access some old software is not a loss akin to forgetting our enslavement of others, and really we need no such memory, we enslave people today.