Why does the loading bar freeze at 80% in Expeditions: Rome?

I remember the first time loading the Rome map; the progress bar froze at 80% for a full minute. It was pure torture. I tried disabling the write cache in Windows, but loading time actually increased by 20 seconds—a truly exciting failure. I used GamePP NVMe Queue Depth Configuration to increase the depth from 1024 to 2048 and performed a TRIM cleanup. 4K random reads rose from 52-58MB/s to 70-76MB/s per CrystalDiskMark, and SSD temperature remained at 45-52℃ per HWMonitor during the test.