Saying TSMC's success is due to their suppliers ignores the fact that all of their competitors failed to keep up despite having access to the same suppliers. TSMC couldn't do it without ASML, but Intel and Samsung failed to do it even with ASML.
In contrast, when Apple's CPU and GPU competitors get access to TSMC's new processes after Apple's exclusivity period expires, they achieve similar levels of performance (except for Qualcomm because they don't target the high end of CPU performance, but AMD does).
Tsmc being the biggest let them experiment at 10x the rate. It turns out they had the right business model that Intel didn’t notice was there, it just requires dramatically lower margins and higher volumes and far lower paid engineers.
In contrast, when Apple's CPU and GPU competitors get access to TSMC's new processes after Apple's exclusivity period expires, they achieve similar levels of performance (except for Qualcomm because they don't target the high end of CPU performance, but AMD does).