It appears that Kizaru's laser pierced the part of Sanji's body that wasn't protected, just as it pierced Kuma. However Sanji, who has average armament, blocking one of the lasers casually with his leg, goes to show that blocking it isn't all too difficult.
Kaido, in addition to being able to tank a laser with his body, may as well easily block it akin to this:
That's probably the reason Kizaru went into CqC with Rayleigh using his light sword, knowing that spamming lasers will be useless, as Rayleigh could simply block and dispel them. Reacting to those lasers won't be all too difficult either; Marco intercepted a Yasakani no Magatama from mid range that aimed at Whitebeard.