About 2yrs ago I booked a flight to my relatives for a Christmas trip and pasted the info into my Google calendar. Within hours, I got google calendar notices about not having confirmed my hotel reservation. It was VERY annoying as it was borderline deceptive, presented as if I'd already gone through the whole reservation process but failed to confirm.
It was definitely a Google notice, and a Google confirmation process when I clicked through to confirm if I wanted this service. I shut it off as best I could find and told them I wanted no part of any such deceptive marketing, even though I would perhaps have wanted a service that made it clear that I was being offered an option, not a fake reminder.
I saw nothing of it since, but then I'd shut it off, so I should have no data. So, it seems that Google has siloed projects that not all employees know about...