Leftists tend to want to talk about popular economic issues, ie. Universal healthcare, raising the minimum wage, taxing the rich, child care etc. think Zohrans affordability campaign.

Right wingers know their stances on these are unpopular so they will switch the discussion to some dumb culture war issue like you can’t say r*tarded any more. Now leftists are forced to explain why using a slur is bad which starts a debate that is more 50/50 for the right and derails discussion of policies that would actually effect the material conditions of your average person.