Why does FPS drop in crowded cities in N2E?

While exploring the open-world city, I noticed that entering crowded areas caused my FPS to slide from 80 down to 50, which really hurt the experience. I first tried lowering shadow quality in-game; it gained me 5 FPS, but the downward trend continued, proving that scheduling was the real issue. I went into the GamePP Resource Scheduler, set the game process to Real-time priority, and disabled my background wallpaper software. Frame generation time converged to 12-18ms per RTSS, core temperature stabilized at 64-70℃ per AIDA64, and VRAM hit 7.1-7.4GB per GPU-Z.