I gave a bunch of details of my personal history to a verification service thinking naively that it would be used to prove I was me.

Instead, they didn't know much about me apparently and just stored what I told them.

Then it appears they were hacked because some completely unrelated release of stolen data included all my data, specifically all that data I had provided to that service, that one time.

The Verification Service is the honeypot for your private information. Arg.