I am interested in why you want to call simulation arguments, Tegmark cosmology, and Singularitarianism theism. I don't doubt there is a reference class that includes common-definition theistic beliefs as well as these beliefs; I do doubt whether that reference class is useful or desirable. At that point of broadness I feel like you're including certain competing theories of physics in the class 'theism'.

So I propose a hypothetical. Say LessWrong accepts this, and begins referring to these concepts as theistic, and renouncing their atheism if their Tegmarkian cosmological beliefs are stronger. What positive and what negative consequences do you expect from this?