I can discretely copy GBs of email messages and word docs in a reasonable amount of time, but I couldn't discretely take cell phone pictures of every page of every one of those messages and documents if I had years to do it. You don't always have to prevent something 100% of the time in every possible situation to have a devastating effect on people who want to do that thing.

I've just provided the easiest example of bypassing any boomer security nonmeasures. give a dedicated and competent attacker 15 minutes alone with your highly secure machine and highly sensitive documents, and if your entire security model depends on DRM rather than actually effective methods, they will figure out how to exfiltrate it all.

In corporate and government environments, I imagine that they'll ban employees / civil servants from bringing camera(phone)s to work, and necessarily forbid them working from home.

The only question is whether they will trust metal detectors to prevent whistleblowers from bringing in these devices, or if they will rely on strip searches and CCTV.

Try to scan banknotes with a scanner and you will see.

Linux/BSD will do it fine.

I thought it was in the scanner firmware.

if you mean there are scanners that prevent you from scanning of a banknote, that's another great example of wasting time, money and resources to accomplish nothing