You can't just spin up a 2nm wafer fab when the latest you've been running is a 300nm process.
Compare: US shipbuilding industry to China or SK.
Factories, tooling, supply chains, and engineering knowledge aren't fungible in the way they would need to be for your statement to be true.
"easily" is doing a lot of work in that sentence. Depending on the good and what they switch to making, this may neither be easy nor quick.