-Brought over a large casual fanbase who are absolute cancer and have no business watching or following any kind of real combat sport;
-Turned the game from a legitimate sport, into a clown show like WWE;
-Forget about attracting fans with your skills and tenacity inside the cage, just talk as much shit as possible outside the cage to make some $$.
-Stalled not one but two divisions for 1-2 years each, refusing to vacate.
-Now has all the champs seeking money fights instead of top contenders.
Did I miss anything?
Without a doubt, Conor Mcgregor has made a largely negative impact on the sport, and has raped its health & longevity. A lifetime ban for this shameful animal wouldnt be enough.