Believing one has a tendency to cause people to fundamentally alter how they live their lives, optimize for an afterlife at the expense of the life they actually have, and then fight wars over the belief that the afterlife is the only one that matters.
As a default state of not knowing, one causes far more material harm in our current reality than the other.
standing on a viewpoint of ca. "the cause of everything is a spaceless, timeless, immaterial, powerful, intelligent, personal being" (ie. the pilosophers' God) does not entail the Abrahamic religions' image of God directly, nor an afterlife of humans, nor a right to self defence, nor commission of evangelization nor jihad.
altough I agree with this datapoint. however the parent post's concern was not about majority, but that monotheism causes violence at all, and it causes more damage to material goods than lack of monotheism.
i once disagree that monotheism, which values non-material things more than material ones, neccessarily leads to destruction of the material. orthodox Christianity for example values material and non-material, soul and body equally.
secondly i disagree that this argument is valid. since if you are in the viewpoint of "all that matters is the non-material" then wasting material does not harm the world. and simirarly, supposedly saving souls at the expense of the body is incomprehensible to the materialist. so the term "harm" understood in 2 disjunct ways per the 2 frameworks.
circling back to orthodoxy: it unites the "saving souls" and "saving forests" (understand well, it's not about trees, but the whole material creation clamped together in a catchphrase) attitudes in the mystery of Incarnation.
As a default state of not knowing, one causes far more material harm in our current reality than the other.