Although Windows has had awareness of the NVMe storage media protocol since Windows 8.1, it turns out that the stock Microsoft driver for NVMe devices, disk.sys, offers suboptimal performance. This driver dates back to 2006, and is part of Microsoft's oldest internal basic drivers. Disk.sys appears to treat NVMe devices like SCSI drives. Microsoft released a new native driver with a greater degree of awareness of NVMe with Windows 11 25H2 (client) and Windows 2025 (server) operating systems, called nvmedisk.sys. The easiest way to check if your drive is using the older driver would be to bring up Device Manager, collapse "Disk Drives," open the Properties of your drive, go to the Driver tab, and click on the "driver details" button.
Notebookcheck made a fascinating discovery that has the potential to unlock greater performance with your NVMe drives, if they are compatible. Apparently, nvmedisk.sys significantly improves performance, both in sequential and random workloads. Using this driver, however, is fraught with risks. Not all NVMe SSDs support it, and if incompatible, it could break Windows 11 boot. The publication put out a guide on how to get Windows 11 to use nvmedisk.sys. This involves changing three Windows Registry values. It would be a good idea to image or backup your data before you tinker with this, so you can perform a full image restore if it breaks Windows booting. The guide can be found in the source links below, use it at your own risk.
Hmmm. The NVMe standard has existed since 2011, and Samsung released their first commercially-available drive with it in 2013. So Microsoft has had at least 12 years to make nvmedisk.sys the standard driver for these disks.
Probably why it isn't standard, especially since there's a driver that does work even if it's suboptimal.
So they can't just write some probe code? It really can't be that hard to determine if there's support.