Even if that one particular instance is false, I seem to remember Target saying their model was too accurate and they were changing how they did things. i.e. Target admitted to predicting pregnancies very well.
Why would they do that, if they didn't think their system was that good?
Maybe to convince other companies to buy Target ads. Advertising companies uptalk how effective their advertisements are to persuade other companies to buy adspace.
Target isn’t going to do something that scares away consumers, like say “our ad tracking is TOO good”, unless there’s another benefit that makes it net positive for them.
Why would they do that, if they didn't think their system was that good?