Hmm. As a chip designer, I think there is no chance this will happen. Running a modern foundry is a huge investment and while they move a lot of silicon volume, it is not enough to support a foundry. Not even close. Second, a foundry is a relatively low margin, high volume, high risk business. That is not the kind of business area that Apple enters. Third, running a modern foundry is an incredibly complex process with a huge level of specialized knowledge requiring years of experience to make it all reliably work with high yield. As someone who has been in the business for over 30 years, I won't hold my breath waiting for Apple to build their own semi foundry.

On the other hand, might they contribute some investment to help TSMC expand into the US or other locales to further improve their priority and pricing? That is likely to happen. They often make large investments to help their partners spool up and meet the required volumes for Apple business.