Caveat that you have to have a device running macOS to do this: If you set up your Apple account to use iCloud to sync your messages, you will end up with your

Caveat that you have to have a device running macOS to do this: If you set up your Apple account to use iCloud to sync your messages, you will end up with your iMessage and text messages in the Messages app on your macOS computer. At that point the message content is easily retrieved from files on disk, should you choose to do so.