The linked question was closed as off-topic.
It simply asked what Trump said on twitter before the content was deleted.
Like it or not (for either reason) Donald Trump is for a few more days the President of the US. Everything he says, particularly on a platform that's been named a government business outlet by the courts, is politics. And "What did he say" doesn't require any speculation or opinion to answer.
While I understand not wishing to give these particular tweets a platform, they were after all removed from twitter for being inaccurate and likely to incite violence contravening their T&Cs. That by itself doesn't make them off-topic.
If as a site we want statements removed from other platforms for being false to be automatically off-topic here, that probably needs to be spelled out explicitly in the Help Centre, and it needs to be reacted to more strongly than with the close mechanisms that leave the content available via a simple link.
Without concerning ourselves on meta with the actual content of these tweets, should content removed from other sites by hosting companies be automatically considered off-topic for Politics Stack Exchange?