You look at a fab landscape where the number of leading fabs has been dwindling as the decades go by, to the point where the only two players left are Intel and TSMC AMD even Intel is clearly struggling to keep up, and you think a good solution is "just build your own fab"? That Apple, with its complete lack of silica fabrication experience, will be the one company or one of the two companies in the world to succeed at staying competitive with TSMC, where all others have failed?
Apple has deep pockets, I'll give you that, but this seems far fetched. If the goal is to keep the US competitive, or to just ensure that TSMC doesn't become the literal only supplier of leading chips, partnering with Intel seems like the obvious choice. It's probably better for everyone if Intel and Apple were to collaborate on keeping Intel's fabs competitive than if Intel and Apple compete for the same US chip fabrication market.