If A is discussing with B their plans for my murder, or creating fictional dossiers of alleged crimes of mine and sending them to police and my employer, or sharing compromising photos without my consent, then ignoring them does not work.

Less hyperbolically, it's only safe to ignore the speech of others against you so long as it has no chance of having an effect. Whether that's through legislation or street violence.

Toxicity is exactly the right word for hate speech, because it can cause hate to spread out in ways that cause real injury or death.