Because everyone sleeps soundly with bright blue LED lighting blaring in their faces.
I fail to see what's innovative about "we shoved business class seats into a narrow-body aircraft".
An A321 is still an A321.
Flying internationally in a single-aisle aircraft is under any circumstances torture no matter how you sugar coat it: "Come fly in our modern, innovative sardine can."
By the way BA did this years ago with their London City A318 which doesn't exist anymore because it was a failure that merely burned money.