Imagine Tylenol is found to cure a disease.

Tylenol is already approved, with known conditions under which it is safe and not safe.

Therefore, it is easier and safer to test a new use for Tylenol than starting from scratch testing a previously unknown drug.

Somewhat the opposite, but can it run Crysis?

Sigh, clickbait at its finest, why else would we click

Digital signature as a means of non repudiation is exactly the way this should be done. Any official docs or releases should be signed and easily verifiable by any public official.