It was part of the same keynote speech where Apple announced their virtual reality headset… so the media largely didn’t cover it.

But Apple absolutely did announce it, and as loudly as they possibly could with a high profile executive standing on stage before a live (online live, but still live) audience of millions of people and every tech journalist in the world to demo the feature. There’s also extensive documentation and whitepapers covering how the crypto works, and I expect it was discussed on public mailing lists ahead of time (I don’t follow those mailing lists - they’re too busy, so not sure about that one).