Tegmark cosmology is not theism. Theism means Jehovah (etc).

The way I read it, it seems like Will_Newsome is not using the word in this way. It may be a case of two concepts being mistakenly filed into the same basket -- certainly some people might, when they hear "Theism-in-general is a mistaken and sometimes harmful way of thinking about the world", understand "theism-in-general" to mean "any mode of thought that acknowledges the possibility of some intelligent mind that is outside and in control of our universe". Under this interpretation, the assertion is quite obviously false (or at least, not obviously true).

I wonder if there is still a disagreement if we Taboo "theism"? (Though your point in the last paragraph is a good one, I think.)