I was partially read up on this a couple months ago.  Part of the issue is that this company has singular knowledge and technology for making smaller chips - 5nm and maybe 2nm?  Point of the article was it would take years to replicate the footprint, equipment, and in-house knowledge to produce at that scale. 

It's a big geostrategic advantage to have that factory on your side of this 'new Iron Curtain' as China tries to project an autonomous economic zone outside of its borders.