I was one of the people affected by this. I spent at least an hour trying to figure out if the paper letter I got was even legitimate, as it directed me to go

I was one of the people affected by this. I spent at least an hour trying to figure out if the paper letter I got was even legitimate, as it directed me to go to a domain I'd never heard of to enter personal details. Eventually, I figured out it was nominally legit, but then I figured out the same organization that leaked my info was asking for more personal info so they could protect me. I opted not to do anything, because I couldn't think of any course of action that would improve the situation, and I certainly wasn't going to voluntarily give Experian any more of my info.