Capitalized text is no easier to read than uncapitalized text.

Maybe for you, but not for me. Capital letters serve as focus points when scanning through text, and appear mainly in the places that people are most likely to be looking for when scanning: proper nouns (to help when backtracking through text to resolve a pronoun) and sentence boundaries (to help find a start point when switching from scanning to reading). Text without capitalization is like text in bad handwriting or a poorly chosen font; missing capitalization only slows readers down a little bit, but that's more than enough to make many people skip reading it entirely.

Absurd. Do you think punctuation is useless and no easier to read? Capitalization is semantics as expressed in syntax; it tells us where thoughts end and begin, important because text doesn't have the vocal rhythms or frequency shifts which we otherwise rely on.