In answer to your original question—
How do you guys handle already leaked online private datas?
To a big extent I no longer bother.
Because everything is out there already.
Birthdates, property records, addresses, everything else.
Put online by county clerks, state boards of elections, local tax collectors, local sewer utilities, etc etc etc etc
Even voter records in many states.
https://voterrecords.com/
So I have full credit freezes with the 4 main agencies (especially after that damn NPD breach).
https://www.cnbc.com/2024/08/23/was-my-social-security-number-stolen-national-public-data-breach-questions.html
Beyond that—we all need luck, and we all need to hope that no one nukes us.