From the article... TU (and the other credit bureaus) decided your PII can be sold without much regulation. Despite laws that require credit reports to have tighter controls. They just say "it's not a credit report; it's just PII" and poof they're magically in the clear.
Because PIs are nominally regulated. It's a popular career with ex-cops who have investigative skills but are over the physical danger aspect of dealing with crime.
Anyone can become a PI in Colorado with just some business cards.
How else are credit bureaus going to make money other than selling this data?
Please tell me this is sarcasm
No, it is a real question. There is a consistent thread of bureaus selling to criminals. It's part of their revenue stream at this point. Doing anything that involved cutting back on this would threaten their profits.