For basically the entire modern history of esports, 1080p has been the sweet spot for competitive gaming. The wisdom goes that a 1920 x 1080 pixel grid gives enough clarity to follow all of the gameplay, while also being light enough that the GPU can process hundreds of frames per second, giving a competitive advantage (or, at least, leveling the playing field).
GPUs today have outgrown 1080p in a big way, though, with flagship cards being able to pump out framerates way above the peak of monitor
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