I don't think that holds water, if they had low confidence the project should have been killed long before they unveiled it yesterday. The inclusion of the 8 is a simple fact that they need to have one model at a given price point.
The X is a luxury item in a sense, and so Apple is probably not expecting huge over the top sales figures, the 8 will be the bread and butter model, but the X is higher tier, lower sales volume, higher priced model.
My point again: the X offers what the competions does. But Apple decided to make it a higher standard. And their normal standard is now below standard.