In this scenario you're talking to someone who already has an established political opinion. Talking to these people is basically useless, there's no way to make people replace their political opinions with some other, new alternatives. They can only do it themselves. The focus should always be on the normies who don't care about politics and mostly repeat the things they've picked up through the osmosis without actually caring about what they say. If their heart is in it and there's an argument, there's no point. Now sometimes it's hard to draw a hard line between a normie who might be open to new ideas and a fossilized chud... Well, sorry, but being a leftist is hard work, get used to it.

Not doing anything is always easier than doing something. And doing something without making a mistake isn't easy, either. It all depends on what you're trying to do. If you're just having a broad conversation about nothing, then it doesn't matter if you agree or not, because there are no consequences, really. And if you're talking to a stupidpol person about something specific, then agreeing/ignoring their opinions will depend on what exactly are you doing. How often are you in a situation when a stupidpol person would be willing to do something lefty but only as long as you denounce minorities? It sounds like a weird hypothetical scenario, it that really something that happens often?

For example, if you meet a stupidpol in a homeless shelter and their stupid opinion comes up, what's the context here? Are they going to refuse giving someone food because they have a rainbow flag pin or something? That sounds really strawman-y, I doubt a stupidpol person would go full cartoon supervillain mode and deny them food or something like this. In this hypothetical scenario, it's more likely they'll might just say something stupid but keep doing their job. So just say something back at them and continue doing whatever it is you were both doing, because what you two are doing is probably infinitely more important than an argument about pronouns.

And if the arguments start flying before any actual work even starts, well, we all know how it's going to go. Things will just fall apart and everyone will walk away feeling smug about themselves no matter what either you or I write in this thread.