China will break the Boeing-Airbus duopoly, not because of Boeing's problems but simply because they will be offering a third option.
They also have the domestic market to support vast sales number even before looking at exporting, a bit like the incumbents have.
Not really. China's attempts to build those kinds of airplanes had been largely unsuccessful so far, and it doesn't look promising. Only the Europeans have been succesful. Airbus is the only one to fear. But that doesn't fit the current Anti-China narrative.
It is time to break the duopoly and introduce competition into the market. It is good for all customers.