Subsidies: doesn't seem China is doing anything the US doesn't do. This morning I read something about how Georgia owes Rivian $1.5 billion in subsidies if they ever build a factory there.
Size: It's clear to me that American carmakers want to sell only XXL cars, I think American carbuyers are more diverse in their preferences.
When I was a kid going with my dad car shopping in the 1970s we saw all sorts of ways that dealers tried to get people into a larger vehicle than they really wanted. I mean, for the dealer, what could be a worse tragedy than a person who could have spent $55,000 on a car walks out with a $25,000 car and doesn't buy another car for ten years?
Before COVID-19 it was common to see a row of 150 pickup trucks or SUVs that nobody wanted to buy at a dealership with a $5000-$7500 discount. Try to buy something compact like a Honda Fit and they have all kinds of excuses why they didn't have any inventory (the factory washed out, yeah right, why are there 50 SUVS made in the same factory that nobody wants to buy sitting in a line) and you will have to settle for a used one at a new car price.
(It is not too different after COVID-19 except that anyone who never shopped for a car before COVID-19 wouldn't remember Detroit's long-time habit of heavy discounts on XXXL cars that people don't really want to buy.)