Risk in hardware is many orders of magnitude worse than in software, so the people making the decisions about what fab to use for a product tend to make much more conservative choices to help minimize risk. Intel as a fab partner is risky. Who in their right mind would select Intel when even Intel's own internal design teams made the decision to outsource manufacturing of some CPUs to TSMC in recent years? Intel has a lot of trust to build amongst hardware designers before that will happen at any significant scale.