I don't think you've grasped the spirit of what I'm saying. In a perfect world, every interaction with a service would require exactly as much identity verifica

I don't think you've grasped the spirit of what I'm saying. In a perfect world, every interaction with a service would require exactly as much identity verification as is required to entirely, 100% prohibit people pretending to be you... but also, people being people, they would then voluntarily avoid interactions which would necessitate giving that proof. In other words, in a perfect world, the government requires LinkedIn and similar services to put users through KYC (i.e. demand proof-of-identity+income for sign-up)... and poof! These services cease to exist, because nobody's going to give them that for only the small amount of value LinkedIn provides people.