Live Captions

One of Apple’s most significant new accessibility features this year is Live Captions, which will allow real-time transcription of any audio content on the device. This includes standard audio as well as the audio from videos and video conferencing apps. FaceTime goes a step further with speaker attribution, so you’ll be able to follow along in group conversations more easily.
Live Captions will be available on the iPhone, iPad, and Mac in macOS Ventura, iOS 16, and iPadOS 16; however, it will be limited to more recent devices across the board. Specifically, the iPhone 11 and later, iPads with an A12 Bionic or later, and Macs with Apple Silicon. It will only be supported for U.S. and Canadian English, at least in the initial release.
It’s not entirely clear why Apple is drawing the line where it is on the iPhone and iPad side, as the iPhone XS/XR also pack in an A12 Bionic chip, but the line for Apple Silicon on the Mac is more understandable.