I don't know - Superman #11 showed how Damian can be gruff but civil during downtime, while their bickering during Super-Sons gets a pass thanks to its anime-ish over-the-topness, having some actual pretty funny lines, and even a hint of self-awareness (using their roughhousing to create a dust cloud to surprise their enemies, which also lends to the anime-ishness). Here his mean-spiritedness doesn't seem to have purpose but to make that cliffhanger happen.