He wouldnt do that because it makes zero narrative sense.
If you guys actually took powerscaling nonsense out ya brains for more than 2 seconds, you'd know exactly why neither Shanks or Blackbeard can lose to Kid or Law at this point in the story
Yes and no.
I consider BB protected .
Not shanks .
FOr me he just got his movie he just said he is ready to go to the one piece so he is fair game now .
Kid or BB Its not that important of who take him out for me in facts Kid taking him ut would contirbute more to the story by giving luffy a realy strong rivals other then BB who is obviously end game.
Shanks is not realy protected anymore luffy goal is to surpas him right ? Well if Kid kill shanks and luffy defeat Kid he would have surpassed shanks .
I don't think kid will kill or beat shanks tought but it is more likely then Law beating BB .
Narativly at least.