The key to defeating Momoshiki (the second time) was damaging his Rinnegan so he couldn't just absorb Boruto's attack.
But now they've gone and given him a special advanced healing ability that instantly fixes burns, fractures, and broken bones.
On top of that, they've given all Otsutsuki innate chakra absorption that can absorb Odama Rasengan on its own, before even considering Momo's hijutsu.
So.....they just retconned in two abilities that would have stopped Momo from being defeated by Odama Vanishing Rasengan.....
This is in addition to the taijutsu skills Momoshiki mysteriously didn't have when Darui was chasing him down.....
Just...