One of the most persistent traps in media analysis and political theory is the Great Man Theory. The idea that history, revolution, and systemic change are driven exclusively by singular, exceptional figures born with divine bloodlines, genetic superiority, or god tier power.
People who write Buggy off as a "gag" or reduce him to a joke are missing the profound material and political point Oda is making. The current Yonko line up is dominated by hereditary or chosen elites. Luffy is the sun god of prophecy from the (Garp and Dragon) Monkey D lineage, Shanks is a literal Celestial Dragon nobility from the Figarland family, Blackbeard is another D descended of Rocks/Davy clan with a "weird body".
Buggy for all his flaws is still a thorn in the Government's side. Causes a breakout of a prison that literally tortures people, rallies them into his army, gets his hands on a Den Den Mushi and exposes Marines during the war, head of an organisation that puts bounties on Marines turning the tables on enforcers of global oppression. It decentralizes power, showing that the invincible machine of the World Government can be jammed, bled, and challenged not by a solitary king, but by the united masses acting in their own material interest.
His charisma works because the masses need a focal point to unite behind. He uses his platform to amplify collective power, proving that the figurehead matters less than the revolutionary mass standing behind him. Oda uses Buggy to tell us that you don't need to be chosen by destiny or born a god to disrupt the empire or wait for someone to. Liberation belongs to the outcasts, the weak, and the discarded when they finally realize that they outnumber the people at the top.