Yes, this is _one_ of the reasons I think TSMC is fairly safe from doomsday theories like China trying to cut it off from the world. Because that would risk it being cut of from ASML, and they are unlikely to be anywhere close to making their own machines before grinding to a halt.
Short term, it's mutually assured fabrication destruction; Long term, the world needs more redundancy and competition in both areas.
But... arent they already cut from ASML?
US disallowed ASML to sell advanced tech to China
Edited to specify China as the one who would potentially cut off TSMC from the rest of the world, which would also cut off ASML->TSMC.
But the majority of chips they need can be built on this process if they have it. They don't need ASML if they got here. And they can't have ASML's new stuff.
Doesn't sound like much of a deterrent.
FWIW, that's about where Intel was 14-15 years ago. That's a reasonable process for lots of logic chips, but not for modern mobile devices or datacenter machine learning engines.
ASML is only relevant to them if they need to get to present day GPUs and mobile devices (as you said) and I don't think that's that important for their needs. But even if it is relevant they have no access to ASML tech because ASML only has that because the basic research is US-owned and the USG will enforce their export controls on ASML and will enforce that critical components are made here so playing nice with Taiwan won't get China any closer to EUV lithography.
What /u/tomxor is saying makes no sense.
TSMC under peacetime conditions has issues obtaining acceptable yields on this equipment. In an armed conflict, there will be no operation at all, much less one that requires a Stuxnet-style attack to shut down.