Not every major product is released without issues, but this is a privacy-related mess/kerfuffle Apple probably would have liked to avoid.
The Houston Chronicle has reported that Apple Intelligence can currently read encrypted Signal messages on under iOS 18.1 iPhone 15 and iPhone 16 models. Signal users looking to keep their content from being read are encouraged to disable Apple Intelligence by going to the Apple Intelligence settings or Siri settings and disabling it from there. This can be achieved by navigating to Settings > Siri > scroll down to Apps > Signal > and turn off “Learn from this app” along with the other two settings.
Apple has yet to comment on this issue.
Stay tuned for additional details as they become available.
Via the Houston Chronicle