I reported plenty of people for a large assortiment of things.
From botters, to people who votekicked because we were after the same loot, people who harass you trough /trade spam abuse preventing you from getting anywhere to even people being total racists.
Not a single one ever got banned. They were all happily strolling around the next hour still, and the day after that, and the week after that, and even now. I dont even feel any of them got a stern talking-to or learned anything. GM's do not undertake any action whatsoever.
But they should! At the very least do more than give an automated response.