Why does Forza Horizon 5 stutter during high-speed driving?

While speeding across Mexico, I noticed jarring micro-stutters despite my PCIe 4.0 drive. I tried disabling all unnecessary startup items in Windows, but loading only improved by under a second, leaving the storage bottleneck untouched. I then used GamePP NVMe Queue Depth Configuration to bump the queue depth from 1024 to 2048 and enabled the high-speed write refresh strategy. CrystalDiskMark confirmed 4K random reads rose to 75-82 MB/s, AIDA64 showed temps at 42-50℃, and GamePP sensors clocked latency at 14-32ms.