[malloreon]

you're making the incorrect assumption that both sides of the discourse have valid positions.

1. what is a non-racist person supposed to say to a racist person to change their views?

2. why is it the non-racist person's responsibility to talk to the racist person? in the words of office space, "why should I change? he's the one who sucks."

[haram_masala]

Let’s not assume that one “side” is racist and the other isn’t. It’s both wrong and unproductive.

[anigbrowl]

But racism isn't being attributed to any particular 'side' by that comment, which raises a valid question.

Racists do exist in considerable numbers and post prolifically online, so what should non-racists say to people like that?

[metiscus]

The 1960s and 1970s saw a reckoning in the USA that while not complete, did result in a number of people with substantially incorrect views eventually coming about to a more sensible position.

Similar victories have been achieved with respect to drug legalization and "gay marriage".

None of these victories are or ever will be complete but a combination of discussion and social pressure did make significant social progress possible.