Why would those pieces of data (DOB, full name, address) ever be sufficient for identity theft?

If that's sufficient to achieve anything then those systems are built on top of hopes and dreams.

>I hope they release a tool to check if I'm impacted or at least email me about it.

"ANTS stated that it is currently in the process of notifying those identified as impacted."

With the number of leaks the French administration had everywhere, you don't need a tool, you are guaranteed to be impacted.

Alternatively, hackers can now be used as a method of age identification.

are govs required to comply with GDPR and data breaches laws?