Yes there are already yom kippur threads but this one is trying to highlight the most important aspect of YK, not general discussions and vertlach etc.
The most important thing on YK may be teshuva and coming closer to Hashem. But although it is the most important thing, it is not the number one on the list. It’s the most important yet only number two. Why? Because Hashem doesnt give kappora ‘ad sheyiratzeh es chavero’. So number 1 is asking everyone for mechilla and only then can we be ready for the real number 1 of teshuva!