Thanks for raising this, @MrsBennetsPoorNerves - we often do take the whole thread down. It’s not always a simple call, though. More often, threads include a mix of views, including posters challenging or correcting each other. As you mention, we’ll remove individual posts that break the rules, and if the overall balance of a thread tips into something that’s clearly hateful or no longer in the spirit of the site, we will remove the whole thing. We also rely on the reports to help us spot when that tipping point has been reached so we do urge posters not to assume it's not worth reporting - it always is, even if the individual post you reported isn't deleted at the time.