Their foundry business is a tiny fraction of their revenue at this point and I'm not sure their overall gross margin is particularly relevant here (also Intel has lower gross margins than AMD or TSMC these days?)
If they can't make good gross margin when making their own products that are higher priced (than similar AMD products)...how are they going to do it when they have to support an end customer that expects high gross margins?
Intel GM ~46% AMD GM ~46% TSMC GM ~53%