Why does Civilization VII stutter during turn transitions late game?

Managing dozens of cities in the late game, I felt a frustrating lag during turn settlements as memory latency fluctuated wildly. I tried forcing a BIOS overclock to 7200MHz, but while bandwidth increased, the game crashed directly at the settlement screen. I used the GamePP Resource Scheduler to set the game priority to Realtime and lowered non-game software priority to Low. FrameView confirmed frame intervals converged from 22-50ms to 14-18ms, with temperatures stable at 54-61℃ per HWiNFO64 and latency at 62-74ns via AIDA64.