But it’s not a debate. They have no interest in listening to you, any facts you present, nor presenting any disputing facts.

the debate is not for them. it is for potential impartial observer who just encountered the problem for the first time and is now forming an opinion.

unfortunately it is really hard, because since the onset of the machine learning generators the pile of crap is literally endless.

But it's not a debate. They have no interest in listening to you,

Adam doesn't debate Bob to convince Bob of Adam's viewpoint. Adam debates Bob to convince their shared audience: Charlie, David, Edward, Frank, George, Harry...

When Bob is ejected from this forum, Charlie, (et al), never hear that debate and are never convinced of Adam's views. They aren't inoculated against Bob's logic. When they come across Bob uncontested in another forum, they may be persuaded; they fall into his echo chamber. When they bring their half-formed ideas back to your forum, they are banned as apologists rather than debated.

Ejecting Bob makes your forum better. Adam debating Bob makes the world better.

The response can also be a closed fist or the end of a bayonet.

Not a first goal, but still a time tested answer.

The response in this context is a preemptive: "not welcome here". We've all heard what the fascists have to say, and it's worthless. Zero tolerance for fascists.