Why edit your post instead of responding? That's such an odd way to do things and breaks the order of conversation.
>Security and privacy are actually distinctly different concepts with very different implications.
True, but you cannot have privacy without security. That is to say, if I pieces my personal information to 5 different groups, but all of them are vulnerable, your data, all of it, is vulnerable, and an untrusted Nth party can attain all of it. On the other hand, if you give all of your personal information to a single secure party, you know who has the data.
Obviously, its a bit more complex than this because often times larger groups are single sources of failures, but still.
For a nondigital metaphor, your list of kinks is less likely to get out if you put it in a safe deposit box than if you rip it into 4 pieces and tell your closest friends to put their piece under their mattress, even if no friend as the whole list and you trust each friend more than your bank, because an adversary can probably figure out that you gave it to your friends, and can break into their houses, but won't be able to crack the vault.
I edited the post because I hit a rate limit on HN. I don't like it either, but I have to choose my use of replies carefully.
The problem you miss is that people have different identities. And people want to interact with others, to communicate with people, through those identities. Locking up your kinks in a vault isn't really an option if you want to share them with a community of like-minded individuals. But just because you do, you don't necessarily want your family to be able to look them up on Google.
People have different even potentially public personas, that they still want to keep separate. Under a variety of names, I'm involved in a variety of different communities, some of which I don't really want people I know IRL to know about, some which I don't mind. But all of them are out there on the Internet, because that's how I interact with them.
Actually, apart from the Google-centric notion of it and the lack of multiple identities (exacerbated by Google's "real name policy", Google+ was probably the closest Google got to getting this right: I could put specify which Circles people belonged in, and share information with each independently.
>Security and privacy are actually distinctly different concepts with very different implications.
True, but you cannot have privacy without security. That is to say, if I pieces my personal information to 5 different groups, but all of them are vulnerable, your data, all of it, is vulnerable, and an untrusted Nth party can attain all of it. On the other hand, if you give all of your personal information to a single secure party, you know who has the data.
Obviously, its a bit more complex than this because often times larger groups are single sources of failures, but still.
For a nondigital metaphor, your list of kinks is less likely to get out if you put it in a safe deposit box than if you rip it into 4 pieces and tell your closest friends to put their piece under their mattress, even if no friend as the whole list and you trust each friend more than your bank, because an adversary can probably figure out that you gave it to your friends, and can break into their houses, but won't be able to crack the vault.