That only works if you can get everyone to stop talking about them. Unfortunately, he has a large enough cult that someone will always be talking about him positively, so the only reasonable counter is to flood the conversation with mockery. Against a more well balanced candidate that would just rankle, but it’s really got under his skin, and under the skin of those who support him, so it’s proving to be a worthwhile tactic.
Maybe it’s just a different viewpoint, but I find the sarcasm of that headline vastly more damning than just saying ‘Trump lies again’. It basically saying that his brain is so fried that he’s unable or unwilling to engage with the reality the rest of us experience.