Even if you can't convince the person you're talking to, it's better to put forward a more coherent message for the people watching. It's always better to have fewer flaws in what you're saying, as it makes it more difficult for people to dismiss you out of hand (even if they're trying to!). There are people out there who value coherency, and a lot more people who'd at least like to tell themselves they do. Having a more factually sound case absolutely does help reach them, and on the internet at least you can never assume none of them are watching. Nothing is lost by not using imprecise and indefensible language, you can still make the actual atrocities involved very clear, and at least some small amount is gained. Given this, I fail to see any reason to engage in those sorts of rhetorical practices