You can't cut costs infinitely. You still need to pay people, suppliers, and above all, people who had nothing to do with the company but hold a piece of paper saying they're entitled to profits.
It's probably the case that you cannot do that enough to compete with the Chinese if you're in the US, so they won't try.
We're in a post-"what about the long term economic outlook of our country"-era and have been since the 1970s. John Q. Public in the US and Helga Öffentlich in Germany don't care that their purchase of a Chinese EV hollows out their country's industrial base, they just care that they spent less on the EV. And why shouldn't they? The countries themselves are lead by people who do the exact same thing on a massive scale.
The US domestic auto industry was hollowed out decades ago. Germany's domestic auto industry is just starting to be hollowed out, that process is in the early days. China's auto rise will ravage European manufacturing, not US manufacturing. Auto manufacturing is a small share of the US industrial base, it's a large share of the German industrial base for example.
Boeing and Airbus will both lose large chunks of their global airplane business to cheaper Chinese competition over the coming decades. It's definitely not exclusive to Boeing. The US airline market is far more lucrative than the European airline market, US carriers like Delta are very profitable and can more or less be forced to not buy from China.
Examples are the strange Japanese flip phones and the computers with CF card and floppy drives with a 1.5 ghz single core CPU selling for twice the price of a MacBook Pro.
With BYD selling globally now, and Boeing losing its reputation, American vehicles of all sorts are at risk.