The Oxford comma debates are a product of (proxy for?) prescriptivism, partisanism, and Puritanism.
It reminds me of the FBI handbook for infiltrating and disrupting organizations by introducing meaningless debates.
It sounds smart.
And the branding enforces that. No one calls it the “serial comma”, which evokes the same pathos as “serial killer”.
It takes a single (extreme) use case as proof why it’s always required. Which is a straw man.
It is a semiotic signaling of identity, akin to the supposed ichtus in the market.
It’s a logical fallacy and sophistry.