Intel’s chances of being a foundry for others are close to 0. It does not matter how good their process technology is. The problem is that Intel was an IP thief in the 80s and 90s; being a foundry requires trusting Intel with the exact IP Intel was known for stealing and nobody wants to take the risk.
There were lawsuits against Intel for IP theft in the news 25+ years ago. It is hard to find articles on them these days as web searches are biased toward recent events, but I was able to find this:
