In ww1 Germany faced similar raw material shortages with ww2. Still was able to produce very competitive fighters to the last day of the war. Fokker dvii and dviii, siemens-suckert DV etc.
In ww2 , from late 1941 , Germany s fighters were badly outperformed by the western fighters. Despite the great potential of both the bf109 and fw190 , the final products that was delivered to the fighter wings were sitting ducks for the spitfires, Mustangs,p47s etc. Unreliable engines, poor building quality, strange aerodynamic choices, poor projects management, lack of two stage superchargers, terrible sacrifice of performance in order not to disrupt the production numbers, unreasonable armament requirements resulted in inferior fighters beyond any hope
A good question is why it took the western air forces 4 years to defeat LW given the huge advantage they possessed not only in numbers but in quality as well.
Really , an American pilot that entered the fight in 1944 , was very easy to score 5-10 kills even if he was not particular talented . If he could be fast enough to score before his comrades. Strafing was the dangerous mission.
On the other hand , even a single kill against an Anglo American fighter in 1944-45, was an amazing succes for a German pilot. The average operational german fighter of the era was 80-100 km/h slower than the p51,spit xiv ,spit ix 25lbs, tempest, p47m , p38l, la7 ,yak3,