yes what you described is how it is right now on youtube, the main reason is to make it look more fluid and natural, apple examples shown mostly work because the overall structure is very static and have a lot of negative spacing. More animations tend to negate the principle described if not done with extreme care.
Thanks @Disposal8433
Yeah, agreed on the JS limitation — right now it only works where the little decryption script can run in the browser, so it’s not truely universal. On the crypto side though, this isn’t meant to be deep security — just casual privacy. The point was the pattern (encrypt locally, store publicly, key in your head), not using AES-level algorithms.