Storing data for decades or even centuries is a difficult thing. But the problem isn't the storage it's the data format!
Who knows if a person 300 years from now has a program that can open .png or .jpg? Or the dreaded .doc and .xls that even Microsoft has problems with today. This poor future fellow probably won't have the capatibilities and might need a few years or decades to develop a reader app.
So ein System erfordert irre viel Aufmerksamkeit von den Fahrern, weil sich die Geschwindigkeitsvorgaben laufend ändern. Das klappt auf Dauer nicht. Die Fahrer würden am Rad drehen (pun intended).