I dont understand some of the Kid fans being suprised.
When Law, Kid and Luffy each got 3B bounty that was a symbolic reflection that Big meme and Kaido combined had 4,388,000,000 B and 4,611,100,000 B which amounts to 8999100000 B so those 3 get a total of 9B which is slighty higher,
so it represents them beating the 2 yonkos
But we know that Kid/Law barely beat BM, so their bounties are inflated af, in reality, Kid is worth prolly a bit less than half of a BM.
So imagine half of Big Mom going agaisnt Shanks, what did you expect?