Pretty much all these sites can view every bit of content you submit to them for moderation purposes. Many of them state your data can teach learning models.
If you really want it private, you don't want it on the cloud/social media sites.
People know what "private" means. If a company calls something private, but it isn't, then they're the ones who need to reconsider what it means, and call their service something else.
A general rule is people don't know shit when it comes to legal definitions. When you have a video it's private to you. When you give that video to a friend it's 'private' between both of you. And when you put a private video on youtube it's 'private' between you and the conglomerate entity of hundreds of thousands of people and all their contractors called Google.
Now the contractor did break the rule and shared it, but your idea of private as no one will see it is the broken expectation.
Yes, indeed, people do know that when I say "I have some private information to share with you", it means I am going to let another party in on the secret.
Pretty much all these sites can view every bit of content you submit to them for moderation purposes. Many of them state your data can teach learning models.
If you really want it private, you don't want it on the cloud/social media sites.