They’re pointing out that Trump wants muted mics because he can’t shut up and won’t be able to stop blabbering. The relatively sane people running trumps campaign know that would be a huge problem because he’s already getting press for babbling batshit and a debate in prime time would be the last place they’d want him to go full demented narcissist.

By making it a news article, Trump sees it and is therefore pitted against his own campaign which he can’t allow, so - it’s win-win and they haven’t even agreed to anything yet.