If a user were to put $1000000 into an account, I would think many would like a took to protect their money more than their anonymity-although it could be encrypted onto the chain of course risking that an attacker could set a 2fa first or that the decryption method wasn't known.

Another possibility would be for the dapp developers (hive.blog, peakd, others) to delay memo messages with certain keywords or lengths until they are approved at a local database level-and prohibit displaying encrypted memos altogether at the dapp level. certainly delaying all memos could affect some dapps negatively.

This of course wouldn't affect the chain at all; the chain would still contain all the bad memos. If someone is technological savvy enough to read things from the chain itself and see all this forbidden content, then we can hope they are advanced enough not to give out their keys.