They made the change last year. https://www.theverge.com/2021/6/7/22522993/apple-siri-on-device-speech-recognition-no-internet-wwdc https://www.theverge.com/20

They made the change last year. https://www.theverge.com/2021/6/7/22522993/apple-siri-on-device-speech-recognition-no-internet-wwdc https://www.theverge.com/2021/6/7/22522993/apple-siri-on-dev... All I know is what I experienced: it got less reliable with the switch and stopped handling stuff it handled perfectly before, then got better with a newer phone.