I have the same problem. My pc has GPU GEforce 4090, CPU intel i core 9 13900K, 32GB Ram, windows 11, monitor samsung Odissey 49" curve. In challenge scenario (KLAX airbus FBW), with ULTRA graphic set, the dev mode shows less 30 FPS (performance unacettable for this kind of PC), while the Geforce app show more than 70 FPS. Which is correct? Is my Pc performing right or there is something wrong?