This isn't a public square. This is a private website. This is not how we decide where our taxes go, nor is it backed by any government.
If you were in public and a person started following you around as you had a conversation (even if that conversation was with everyone in the world except the bad actor) you could walk away and take the conversation with you.
If the harasser kept following you, you could firmly ask them to leave you alone, then start creeping your hand toward whatever weapon you keep on your person.
According to you, a person should not be able to post their Eid spread without every reply in the thread getting @ed Islamophobic venom?
A person cannot ask for latke recipes without everyone who has one being @ed antisemitism?
A woman cannot post a thread about a great picnic she just had with her wife without everyone replying "Nice cheese spread!" being bombarded with @s calling the women in the OP men?
Do you see how your—in my view, flawed—position sures up dominate power structures and discourages identities which are marginalized (and tend to be the victims of harassment) from speaking?