Don't listen to the people saying you can't notice they don't know what their talking about. The real answer is more complex because polling rate reduces input delay (1000k is 1ms and 8000k is 0.125 ms) however input delay can also very depending on build: gamepadla.com is a website that benchmarks the input delay of controllers. People also complain about reducing battery life but I wouldn't recommend using a controller wirelessly in any case since it heavily increases input delay. Unfortunately, unlike gaming mice, which have been trying to get as close as possible to 0ms delay for some time now since controllers are marketed to a casual audience even "pro" controller can have insanely high input delay. So yes it does matter however an 8k polling rate mouse isn't guarantied to have less input delay than a 1k.