Wall Street want to see Apple keeping up with others. If they don't, they'll downgrade Apple's stock. Apple is moving in last, because they know AI is not worth anything so they ride the final cycle of the craze and write it off as cost. Same thing happened to VR/AR.

An existing system isn’t being replaced though.

There was no prior system in Apple Mail to detect priority emails.

The new opt-in feature is not responsible for spam detection. This is a failure of the existing spam detection classification.

When you have a hammer everything starts to look like a nail. We have LLMs, now we need to find a use for it in a way that people are willing to pay money for.