They’ve been growing an economy-of-scale advantage with their ever-more-capable SOCs in both phones and computers. They got their wired protocol accepted by the entire industry, and now are going to destroy whatever’s left of the already thin margins of its hardware competitors, which has been likened to the margin on bananas.
Most CPU production is in Asia, regardless of manufacturer — apart from Intel, which is going down the memory hole faster than the Russian space program.
They’ve reserved most of the manufacturing capacity of TSMC’s 5nm process, and TSMC is going to roll out 3nm — Apple has reserved that as well. The projection was that Apple was buying more than half of TSMC’s entire production capacity for 2021.
AMD also avails itself of TSMC’s OEM capacity, btw.
https://www.gizmochina.com/2021/02/08/apple-tsmc-5nm-chips-2021/
https://samagame.com/en/apple-reserves-all-of-tsmcs-production-capacity-for-3nm-chips/