Breaking this down
1 ) the fear of the laser you showed in your post are a bunch of non top tiers , of course lasers are harmful to Weak chrs and to someone with rare scenarios to get effected by lasers
I am showing lasers you are showing kicks, are you slow?
Sanji was damaged by kizaru's kick and so did luffy.
I don't think Kizaru one shots whitebeard unless he tags his head directly with a laser beam. WB will endure it if it is not too direct but this will be deadly damage