Why does web-swinging in NYC cause random freezes?

The power fluctuations of this PSU are maddening. Swinging through NYC caused 0.5s freezes with NVMe latency jumping to 20-50ms per CrystalDiskMark. I tried forcing PCIe 4.0 mode in BIOS, but the system wouldn't even boot, which made me absolutely furious. I used GamePP NVMe Queue Depth Configuration to increase the depth to 2048 and adjusted the write cache strategy. Random reads improved to 68-75MB/s per CrystalDiskMark, and SSD temps stayed at 42-50℃ per HWInfo.