Apple also funds much of TSMC's growth, without any pathway to ownership. Apple is likely just buying top priority.

Let's be real here, TSMC's growth is there with or without Apple.

It’s not obvious it would be had Apple not started pumping stratospheric amounts of money into them years ago. And they’re still pre-paying new fab development that TSMC might find it challenging to afford without them.

(Disclaimer: casual observer at best. May be misrepresenting what I’ve heard.)

That's not clear at all. TSMC's capability growth _started_ with Apple fabbing with them

Apple prefers to keep away from the downsides of actual ownership while having the upsides of being an only customer

Does anyone prefer to keep the downsides? The only thing stopping people is not having the cash to be able to do the same.

There are a number of companies that can goe toe-to-toe with Apple that don't have the same approach, even if they can afford to. Apple and Walmart are known to put the to put on thumbscrews on their suppliers more than fellow behemoths in their respective industries.

This makes me think it's less of an affordability issue, and more of where they fall along spectrum on amount of margin that can be squeezed from smaller suppliers.