[gaspard234]

>I know biometric data is intrisically secure.

I work in security (at a crypto/web3 company!) and the opposite line of thought prevails in the field, most security experts argue that biometric data is fundamentally insecure especially for auth. A quick google search shows a lot of research backing that, from universities to major tech companies.

>Using ZK-Snarks with biodata allows you to verify, profit and protect your data. Instead of handing it to some entity to do god knows with.

How is this going to happen exactly? The requesting entity, like a doctor, asks for medical history. I use my retina to verify, and thanks to ZK-Snarks they have no knowledge of my retina data. How are they going to get the blood pressure readings? They need the data to analyze and understand. And what stops them from saving it in their own DB?

Similar with many of these web3 products. Think, uniswap or defisaver. Ok you can use ZK to auth, they have no idea what wallet address is connected. But as soon as you use it they know exactly who and what you transferred and traded, all stored in a DB.