Totally different geo area to cover and defense strategy comparing NATO/US to China.China actually has more twin engine Flankers and J-20’s than single engine J-10’s. This is the opposite of the US that has more single engine fighters rather its the F-16 or the F-35 than twin engine fighters like the F-15 or the F/A-18. And most NATO countries don’t even have twin engine fighters just the single engine F-16 or F-35. It makes sense since singel engine smaller fighters are cheaper to procure and to operate. China should have invested in developing a long range bomber and have fewer Flankers and more J-10’s in her fleet.
The fleet in my view should have been two thirds J-10’s and one third being J-16’s and J-20’s. But China lacks long range strike platforms and the H-6 is showing its age so China has to compensate with Flankers.
The US has bases around the world and close distance between Euro countries VS China's area denial to 1st island chain and South China sea.
China need twin engine plane 2:1 to single engine plane, not the other way around.