KiwiFarms has a policy against illegal behavior. If your argument is that having a policy and half assing it is sufficient for Twitter then you should be consistent and allow KiwiFarms the same excuse. The size is irrelevant. If anything it should mean Twitter should be held to a higher standard due to the sheer reach of the platform. Twitter has significantly more resources to stop this behavior through both automated and manual processes. Stop justifying Twitter's complete and utter failure.
KiwiFarms has removed posts that were doxing people in the past. I am not sure how frequently they do it though, but since they do it sometimes 'half-assing' seems appropriate.