China is not the UK, and isn’t comparable, any more than the US was. Apple’s manufacturing is far more dependent on China than it is the UK, with one exception: Arm. Legitimately, if the UK government declare Arm to be unexportable to the US, they can completely fuck over everyone except Apple, who I expect has a Complete Code license or equivalent so that they can continue development of Arm goes bankrupt or gets cut off from international trade.

A better question that supports the point here is:

Which of the world’s countries are able to materially damage Apple’s ability to transact business in other countries?

Those countries hold serious and real leverage over Apple, because Apple can’t just walk away from doing business in that one country without having their business impacted elsewhere. The UK is not on my version of that list, but if you’ve a good reason why it should be, that’s the missing data here and that’s invaluable leverage to recognize. (It may well also already be documented in Apple’s financials.)