Was asked my opinion on this on
my wall, and I'll mention some relevant bits here
"I didn't see any evidence of this being a legitimate gravity wave phenomena other than Might Guy bending space trough speed. So I don't see how the argument doesn't come down to anything other than that (Might Guy bending space through speed), regardless of how much you claim it doesn't."
"It being actually stated to be a gravitational wave would be enough for me."
"Performing a physical action to make space distort is a common trope in fiction, it's a giant stretch to say a scene is actually portraying gravitational waves just for having a scene where someone moves so fast that space starts to bend."