Let's not be too dramatic, ascii and utf8 will be readable in 250 years, that's a certainty. As for the hardware issue, his notebook was kept because he was an

Let's not be too dramatic, ascii and utf8 will be readable in 250 years, that's a certainty. As for the hardware issue, his notebook was kept because he was an important person. Average Joe's notebook had a much greater chance to go into the landfill. That's the same for today persons' digital files: Average Joe laptop goes to landfill but I'm sure presidents and whatever's files are archived by State or their families, same as they did for the paper notebook back then.