I think this is ridiculous. No country should be able to "read" a stamp/visa in your passport except for the country that put it there, because no country has a need to know what other countries you've been to, period. The only legit reason to "read" a stamp would be on exit, to see when you entered that same country, and to see your history of visits, again, to that same country. China should only be able to see your China passport stamps and visas and nothing else. Rejection based on where you've been in the past ought to be illegal under international law but since it's so easy to come up with other excuses for rejecting someone, this should be enforced with technology that makes it impossible to "read" a stamp that was placed there by another entity, through cryptography. Any stamp placed in the passport should be encrypted with the country's public key so that it can only be decrypted/read by that same country, by using their private key. Any other entity trying to read that entry would find it to be unintelligible.