It gives end game players something to do, and they're cool fights I like them. The lack of motivation to do them is in my opinion directly tied to the rewards. While they are amazing lockstyles, they are just lockstyles and only for sword using jobs. Unless rewards that you can use toward other in game goals are also included in the drops then I don't think it will gather traction quickly. (Things like linen's etc in enough quantity to justify the battle requirements).