If your kid grabs your gun and shoots itself with it, it doesn't really matter if it's your responsibility, your kid is still dead.

Now change the gun for a radioisotope powder, or a vial of pathogens, and it doesn't matter it was ultimately your responsibility - hundreds or thousands or millions of people are still dead.

That's why normies do not get to play with toys whose lethal consequences scale far beyond the irresponsible users.