It gets always said that decentralised applications have better privacy than web2 application because we do not have evil central parties tracking our data anymore. But if I see it correctly, all the data in a decentralised application is stored on the blockchain such that anybody can read my data. That way there is no privacy at all and every evil party can do whatever they want with my data. Is the data encrypted, or what and if so how can someone share data then?
Am I wrong and if so explain to me why?