It's a shockingly common source of data leaks. There are some versions with more subtlety, like actually redacting the text but a copy of it remains in the file for version tracking, as a separate layer, or things like that.
PDF is derived from printer control tools, and has a lot of features built in that add flexibility for office document purposes, but can be surprising for people not expecting it.If you're working as a team to redact documents you might deliberately use something reversible so that the person checking your work can 1) see what you redacted 2) unredact if they think you shouldn't have.Sometimes people also just don't know there's actual reaction tools built in.
The part that I'm more surprised by is that whatever process they have for releasing documents didn't involve passing it through a system of some sort that automatically fixed that sort of thing.
"wished on the wrong party" is a funny way of saying "advocated for hatred and oppression". And you're leaving out the part where what's happening to them is what they said they think should happen.
It's hard to have sympathy for someone being treated how they thought others should be treated.I do however have enough sympathy that I've consistently done everything in my power to keep it from happening to them.