[dantillberg]

How is this a violation of the friend's privacy?

The friend shared with Facebook, and Facebook intends to store the data forever. The friend shared via Facebook with the GP, and GP could go and read/view the data as often as they wished via Facebook.

Yes, GP shouldn't subsequently share this data with other parties, and GP should take care to secure this data. But why shouldn't GP store the data for their own use, though? Is this any different than archiving emails from the friend?

[wormseed]

Facebook deletes the data when a user asks. OP is explicitly trying retain a copy of people's data against their wishes.

[jyrkesh]

When you share something, whether it's publicly or within a closed loop of social media, it is inherently not within your control anymore. You can NEVER create any kind of guarantee that clicking "delete" erases every potential copy of the data. Folks need to have that in the front of their mind when they create and share data on the internet. Full stop.

Now, morally, I could maybe understand where you're coming from. It's more of a "jerk move" than it is subverting a technical promise.

But I backup my Telegram messages occasionally through their data export tool. Are you proposing that I cross-reference my own backups with messages that get deleted from our chats? Same thing with WhatsApp.

Assuming I'm not commercially monetizing those backups, I consider it well within my rights to have a copy of conversations I've held with people in the past. And in fact, it may be by design that I don't want them to manipulate the "cloud copy" of our conversation in the future.