how does putting the vide on chain, etc... gives the ability to verify if it's real or not? heard a lot of people talking about this, what's the best thing to read on the topic?

how does putting the vide on chain, etc... gives the ability to verify if it's real or not? heard a lot of people talking about this, what's the best thing to read on the topic?
https://twitter.com/shaunmmaguire/status/1758197940253000056

Two key aspects here: identity, which establishes credibility, and authenticity. Cryptographic signatures verify that the uploader, say a news anchor, is genuine. And for the content itself, AI can determine if it’s been tampered with or is AI-generated.