1) The spec used to require Theora support. Apple said they wouldn't
support Theora, even though the spec required it at the time. Therefore,
the lack of a requirement cannot be why Apple doesn't support Theora.
2) When the requirement was removed from the spec, the reason given by the
editor was explicitly that Apple did not support Theora. Therefore, this
was the cause, unless you want to accuse Ian of lying. (Do you?)
Apple never asked for the requirement to be removed, as far as I know. They
just said they would ignore it if it wasn't, so Ian made the decision to
remove it.