> This is from a dissenting opinion of a US Supreme Court justice

No, its dicta which neither was part of the substantive ruling nor an accurate description of pre-existing law from the Court’s opinion (which was unanimous, so there was no “dissenting opinion”) in a case that has since been overruled and is notorious for having allowed an egregious restriction on core political speech.

Maybe people keep using it because it makes a lot of sense to them, whether or not it's accepted (US) case law or not.

> yet keeps coming up as an example of speech that's permissible to suppress for some reason

Because they don't actually have an example of not imminently violence causing non-fraudulent speech that SCOTUS has upheld a ban of. And then when you call them out they'll say "but wait, it's metaphorical". If they had a better example they'd be using it.

Child pornography

Child sexual abuse material is evidence of violence, and act of violence, all at once.

So are videos of people being punched and stabbed. Those are legal

The sharing and owning of those videos aren't part of the violence as they are with CSAM. That feels evident, right?

Can you explain why?

Thank you, I wasn't aware of that.

Regardless, incitement remains an exception to free speech the world over to some degree. Article 20 of the International Covenant on Civil and Political Rights holds that incitement to discrimination is prohibited, for example [0].

My point stands, people of most societies globally believe certain speech should not be protected.

[0] https://www.ohchr.org/en/instruments-mechanisms/instruments/...