I dont have to debate how much it matters, I can look at top dungeon content and see that it clearly doesn't matter as much as people say it does in these conversations. If it did, if free movement was the be all end all then BM hunters would dominate keys, and even more as you go higher, where massive packs exponentially increase the necessary movement and the large pack size plays well with their uncapped aoe, and yet the data does not reflect that.
At the level of play where the movement is a massive boon no one's playing super well, and at the top levels you stop seeing many hunters, cuz when the hits get heavy they all fall over.