It seems like you missed the point and illustrated it at the same time.
The point is to maintain quality discussion. Discussion of politics is notoriously shitty. Then you came in, had a few political discussions of low quality, and that is why we have the custom.
There is other discussion of the disadvantages of the norm. In particular, I direct you to the conversation surrounding the Lesswrong/Lesswrong 2.0 change.
It seems like you missed the point and illustrated it at the same time.
The point is to maintain quality discussion. Discussion of politics is notoriously shitty. Then you came in, had a few political discussions of low quality, and that is why we have the custom.
There is other discussion of the disadvantages of the norm. In particular, I direct you to the conversation surrounding the Lesswrong/Lesswrong 2.0 change.