Why does Civ VII freeze for 5 seconds during turn transitions?

I was managing a massive empire with hundreds of cities, but I felt total frustration when the system entered a 'fake death' state for five seconds every turn. I tried installing the game on a SATA HDD for comparison, but loading times actually doubled, which just proved the issue was concurrent I/O processing. I used GamePP NVMe Queue Depth Configuration to raise the queue depth from 32 to 128 and enabled write cache merging. CrystalDiskMark confirmed random reads rose from 65 to 82 MB/s, AIDA64 showed I/O latency at 12-45ms, and HWMonitor kept temps at 48-55℃.