Another good reason never to write on the back of one's index cards is that it precludes the necessity of scanning the backs of cards for complete digital back ups.

Without this one would need to scan all the backs and either handle the special cases of cards which did have backs or removing "blank" cards after the fact.

Harold Abelson, Ross Anderson, Steven M Bellovin, Josh Benaloh, Matt Blaze, Jon Callas, Whitfield Diffie, Susan Landau, Peter G Neumann, Ronald L Rivest, Jeffrey I Schiller, Bruce Schneier, Vanessa Teague, Carmela Troncoso, Bugs in our pockets: the risks of client-side scanning, Journal of Cybersecurity, Volume 10, Issue 1, 2024, tyad020, https://doi.org/10.1093/cybsec/tyad020

Abstract

Our increasing reliance on digital technology for personal, economic, and government affairs has made it essential to secure the communications and devices of private citizens, businesses, and governments. This has led to pervasive use of cryptography across society. Despite its evident advantages, law enforcement and national security agencies have argued that the spread of cryptography has hindered access to evidence and intelligence. Some in industry and government now advocate a new technology to access targeted data: client-side scanning (CSS). Instead of weakening encryption or providing law enforcement with backdoor keys to decrypt communications, CSS would enable on-device analysis of data in the clear. If targeted information were detected, its existence and, potentially, its source would be revealed to the agencies; otherwise, little or no information would leave the client device. Its proponents claim that CSS is a solution to the encryption versus public safety debate: it offers privacy—in the sense of unimpeded end-to-end encryption—and the ability to successfully investigate serious crime. In this paper, we argue that CSS neither guarantees efficacious crime prevention nor prevents surveillance. Indeed, the effect is the opposite. CSS by its nature creates serious security and privacy risks for all society, while the assistance it can provide for law enforcement is at best problematic. There are multiple ways in which CSS can fail, can be evaded, and can be abused.

Right off the bat, these authors are highly experienced and plugged into what is happening with technology.

It took four months for Hanna BredenbeckCorp, a project assistant for the Smithsonian Institution, to scan all of Phyllis Diller's joke cards for subsequent transcription and creation of a searchable digital database.

I do scan them, though in a somewhat different workflow than the batch processing that some might imagine. The broad outline and some of the specific details can be found here: Handwriting my Website with a Digital Amanuensis. The comments section of that post has some useful tips for folks on other platforms.