@MisterShin: Yeah, because its physically possible to catch beams -_- lol but nope, that just means they werent moving at light speed, nor were they made of light. The lasers in OP come from Kizarus laser which comes from the light light fruit (or whatever its called lol) plus even if it isnt light speed, it has been calced AT LEAST 30 mach, nearly twice as fast as mifune has been supposedly calced as. also, while it's not island busting, it has been said as town level of destruction. He cant one shot an island, but technically if he kept going he could destroy it like he did with noah, only being stopped by shirahoshi. i dont think black star could tank nor live through a continuous elephant gatling.
people still seem to forget luffy has a great advantage with his observation haki, and can see his attacks coming before he uses them