Wouldn't the "idea" of nihilism, of a nothingness, be also a full "part" of the totality of becoming interdependent arising? I say "part" lightly since language is generally used to imply reifcated ideas are a absolute construct. No conclusive point of a thereness or non-thereness of anything can be made since there is no conclusive point that can be made of the selfness of anything, a person-self, a rose-self, or in this case, a nihilism-self. Nihilists "or" Materialists are fully "part" of a "true self". Form is emptiness, "nihilistic view on existence is emptiness". "materialistic view on existence is emptiness", both statements would be "true" due to no ultimate dualistic barriers that separate "them" in a borderless interdependent arising.
Even holding the reification of a idea, the rigid belief of a conceptual essence is emptiness, no?