Which shows that it is fairly strongly "unique", since no-one else has used it and been pwned (or he hasn't reused it and been pwned).
It's great that sensitive breaches are apparently hidden but I'd be wary of judging for other people what is sensitive. Some like Ashley Madison are obvious, others less so.
Actually, I don't understand your comment.
You can download all the hash files if you wish to run purely locally.
Also the site hosting Troy's list is Cloudflare. Cloudflare act as a https proxy for a large number of sites, so they already have access to a large number of passwords.