I worked with IBM in the early 2000s porting some IP to their processes and what was so difficult was that everything was proprietary to IBM. From the nomenclat

I worked with IBM in the early 2000s porting some IP to their processes and what was so difficult was that everything was proprietary to IBM. From the nomenclature, to the tools, to the models, etc. That was great when they were on top, but the world passed them by and there was no hope of converting them over. I never worked with Intel the same way, but some close friends did and it sounds exactly the same. They are proprietary and very inefficient. A block that would normally be laid out in two days, Intel would spend two weeks on. Their process design rules were super restrictive and their tooling just isn't efficient compared to the what the rest of the industry now uses. Unique, strict and obnoxious design rules might be OK when you are designing a high-volume processor like Intel, but that is not the kind of process you want for a foundry. I fear it is not in Intel's DNA to make this switch.