It was still an attack with the intent to kill, and sengokus casual attacks were nearly one shooting Shiryu and the likes.
Fusen is a solid defensive ability like Choppers guard point imo afterall, it allowed Luffy to fully negate the damage from a superior attack from cracker when a casual one almost chopped off his arm.
But it’s definitely not a good look. As i said, I appreciate the callback to Skypeia, but I wish he used any other move than Hells Memories