That seems wildly optimistic. I can think of various provisions under GDPR that make this perfectly fine.

For example, purpose limitation allows for compatible processing, and parsing calendar events to allow for queries like “when does mom’s flight land” is absolutely covered under that.

And, of course, GDPR doesn’t require consent. Performance of a contract is a perfectly valid legal basis other than explicit consent, and the operating system terms of service you agree to when upgrading or setting up a new device will cover this.

On a side note, you don’t want GDPR to work the way you think it works unless you really want cookie consent banners dialed up to a million.

None of this should be construed to mean that I like this feature in macOS or am defending it. I’m merely pointing out that this interpretation of GDPR does not match reality.