This rule applies only to the AskLemmy community. A ban on US politics posts in AskLemmy makes sense for several reasons:
US politics tends to dominate many online spaces already, drowning out other valuable discussions.
Political discussions, especially about US politics, often become heated and polarized quickly, which can detract from the thoughtful, contemplative atmosphere that open-ended questions are meant to foster. When people discuss US politics, they tend to take hardened positions rather than engaging in genuine exploration of ideas.
US political discussions often fall into predictable patterns and talking points, which goes against the spirit of having thought-provoking questions. The same debates tend to play out repeatedly, offering little new insight or opportunity for meaningful reflection.
A community focused on open-ended questions should ideally have a global perspective. US political discussions can make the space feel less welcoming to non-US users who might have fascinating questions and perspectives to share about their own cultures, philosophies, and experiences.
There are other communities whose purpose better aligns with discussions about US politics.
People need some communities where they can engage with others and NOT have to see or think about the recent election.
Nobody wants every community to be a free-for-all about every topic. Please feel free to discuss US politics in a relevant community about the US, about politics, or about world news.
!politicaldiscussion@lemmy.world seems like a good place to redirect those conversations, maybe you could consider adding it to the sidebar, should the rule become permanent?