Only about 7% of mentally ill patients ever seek help. So that leaves 93% of the mentally ill who would be unaccounted for in a database of the sort mentioned.
The 7% who do seek help are most likely the least ones in society to be violent.
They just know too much to resort to that sort of thing physically.

I guess the writers must be assigned articles to write and search for ideas which are
sometimes ludicrous.

The statement about being in Germany during the Hitler regime is very applicable
to the idea of database for patients with mental illness. Ridiculous, in my view.