The topic arguments: WB could sink the pirate island from afar, right, let's suppose he could do that, minimizing his losses as much as possible and killing almost all the BPs, so his main reason for not going to WANO would be resolved, but according to the CANONE of the manga we read, the WB, who thought several times along with the members of his crew about going or not to WANO, decided not to go to WANO because according to MARCO, the outcome of the battle was something indefinite and the losses would be great.
So somehow they assumed that the members of KAIDO+ could handle the WB HEADCANON of sinking the island of the beast pirates at long range,that's what the kaidou intelligence system at the entrance to the WANO country is for, to identify approaching threats and take measures to contain them.
"Bullet explained how to become the strongest, and that was defeating admirals and emperors", but WB never beat KAIDO, BIG MOM, SHANKS, Admiral GARP and SENGOKU and even KONG... and yet it became WSM.
"Oh but BIG MOM and KAIDO would need ancient weapons to conquer the world",
The world = Shanks, BB (two Yonkous), Marine + Ssg, Shichibukais, Government, Revolutionaries, countries that oppose, and indeed strategically speaking, getting the ancient weapons is the best option strategically, for anyone who reads KINGDOM and knows the basics of wars will quickly realize this.
Conquering the world means going over all of them and not just one organ,what the LARINES think is that the alliance of KAIDO and BM was being made precisely to destroy the navy and only that, that's the sad mentality they have.