It is already. You can buy it online. There is not a lot of places where hackers sell that kind of stuffs.

1k lines are already shared, seems legit. Most of them is just <30k€ people. Only a handful of millionaires (8 >10M if I remember correctly), 0 billionaires. 2/3 people, 1/3 pro, there is no information about tax of professionals.

Seems to be an API endpoint about people who ask questions to the DGFiP.