There's an old adage from way back when the internet was new: if it's online, it's as good as public.
There's second adage from the same time period: don't say or do anything online you wouldn't be comfortable saying or doing in front of a roomful of strangers.
Cloud computing is online by definition. So... who's surprised here?
There's a reason why I never, EVER do anything in the cloud unless I'm forced to. That includes privacy-invading chatbots run by abusive Big Data monopolies.