I think you are missing the point that many have been trying to convey. It's not about whether China already has a finished product. It's about China is making nice progress. And China has gained confidence that they can do this themselves. So they won't waste time and money to get something that they are confident that they will be able to make.
It's like you coming home and your wife is still cooking a fancy surf and turf dinner. The steaks are on the grill, salad is in the bowl, baked potato is in the oven and lobsters are in the pot. However, nothing is on the table yet. So what would you do? Patiently wait for your wife to finish everything and enjoy a nice fancy dinner? Pick up the phone and call a pizza delivery while completely humiliating and embarrassing your wife?
This is exactly what everyone has been saying. Not that China has gotten a polished engine. But that China has something very promising cooking in their oven. The Chinese govnt has confidence in their engineers. And also, they respect their engineers. And we should too.