I don’t have the same experience.
I’m getting about 36fps (half locked from 72 on pimax) in 2024 with all settings maxed except LOD for terrain and buildings which is 80t/50b atm and traffic car/plane/boat on low. Render res is 85.
I get a bit better than that with similar settings in 2020, yes. Without comparing exactly, the big difference in 2020 is that my render res is 100 compared to 85 with about the same settings and slightly more fps.