Why do scene transitions lag in Mass Effect (New)?

Loading bars stalled in ruins because the default NVMe queue depth of 64 was too low. I bumped it to 128 first, but saw no improvement. I used GamePP NVMe Queue Depth Config to set it to 256 and enabled TRIM. CrystalDiskMark showed 4K random read speeds rising from 50MB/s to 75MB/s. Transition time dropped from 8s to 3s.