Earlier quoted context omitted.
Funny, I read it the opposite way: as a wry and pithy way to say "FINALLY goddamned Siri doesn't just hang around and try to parse noise, which has been annoying all of us at Apple as well for ages." Not that one or the other of us is "right" it's just funny that a short sentence can be read many different ways.
Yeah, but they didn't fix that problem, they just made a way to override it.
Sure, that's not the same as solving the technical problem of "when to stop listening". But it's solving the user problem of "it doesn't know when to stop listening". And it's not some explicit additional button you have to press to override any default behavior. It's implicit in the new method.
Unless the former UX is still around and this is an additional, optional, pattern. But that seems ... not very Apple-like.