I think the GP misspoke when they said "option traders". Market makers want to be delta-neutral -- they don't want to care whether the underlying goes up or dow

I think the GP misspoke when they said "option traders". Market makers want to be delta-neutral -- they don't want to care whether the underlying goes up or down, since they buy and sell both puts and calls and profit from the bid/ask spread. Your description is right(-ish) for directional traders.