Reinstalling makes sense. The behaviour of the sqlite3_key API is to fall back gracefully to plain text databases if the sqlite implementation does not support encrypted databases. This explains why iOS 15.2 can't open an encrypted database. By removing the app you are deleting your encrypted database and by reinstalling the app iOS 15.2 is creating a plain text database. You can confirm by extracting the iOS 15.2 database file and opening it in a text editor.
It would be nice to get a definitive answer on what version/flavour/encryption methods of SQLite are supported on different iOS versions.
KevTheDev
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