https://thenextweb.com/privacy/2019/10/11/apple-might-soon-allow-you-to-delete-siri-history/

Apple has officially begun testing a feature that allows users to explicitly opt out of sharing audio recordings to improve its Siri voice assistant.

The update — available as a beta for iPadOS 13.2, iOS 13.2, Apple tvOS 13.2, WatchOS 6.1, and MacOS 10.15.1 — will also make it easy to delete their Siri and Dictation history, allowing users to erase all the Siri data Apple has on its servers.