I also have a Ryzen 7 9800X3D and an RTX 4090 - CPU is definitely not too weak. I’m running a 240Hz monitor, and 240Hz is set in Windows. Overall, I don’t have FPS issues (apart from the SU4-related problems).
However, I have my FPS capped at 60, because for virtual flying you don’t need 200 FPS. Locking it at 60 takes some load off both the GPU and CPU, which results in a smoother simulation. I should also mention that a new NVIDIA driver was released today, and I’ve already downloaded and installed it without NVIDIA app and NVIDIA Audio.
Some recommend using DLSS, but keep in mind that it generally causes noticeable image degradation (at least to my eyes), so I stick with TAA.
Also, Frame Generation is basically just fake frames - my eyes catch them right away. But if someone doesn’t notice the difference, sure, they can play with DLSS and FG enabled. Unfortunately, I can’t.