I think both of you had it turned on from past OS installs - it's bundled under other search metadata, the config isn't new to 18. And "it's on and I don't remember agreeing" is absolutely not evidence. This is super common - nobody remembers what they enabled a year ago.
Think about it this way: for people who turn off any & everything that phones home (aka anyone who is frustrated by this new "feature"), the chances of them having turned on something like that upon install is almost nil.
