>>2923Public key encryption is cheap especially when TLS uses it so even web browsers already have that function and there is a Web Crypto API. Why would it be expensive?
https://developer.mozilla.org/en-US/docs/Web/API/Web_Crypto_APIThe only issue is making sure the user is not dumb and actually has the private key on demand. Good luck ensuring that. And because of that, I don't think it works.
I think doing a one way encryption with well known advanced algorithms is enough. Consider that PBKDF2 based on SHA2-256 is well known and used in the aforementioned Web Crypto API.
https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto/deriveKey#pbkdf2Just using basic principles to reason using thermodynamics means you have to use more energy than a supernova from an average sized star to brute force SHA2-256 has stood the test of time for 20+ years. Unless we get quantum computers worth something other than being able to generate citations in research papers, I expect it to keep standing the test of time.