What is a word for a topic or social discourse that has been spoken about too much? Often these topics generate a lot of heat, in media and on different platforms, without making any distinct progress. Various individuals will pronounce opinions and bring out the same argument points over and over. Many examples can be found in current affairs (e.g. immigration, religious radicalism, etc.).
The topic might be a dead horse.
To beat a dead horse is to overwork the topic. However if you ae overworking the topic deliberately, you can always claim that:
"There is no horse so dead that we can't beat it one more time."
A term often used on the internet is flame war - an argument that has been had many times and is certain to rile people. in this case, there are two sides to the story and everyone is convinced that their side is correct. I'm not certain that this term has a wider (meatspace) currency, though.
Moot topics : debatable or disputed topics with very little practical outcome dictionary