Microsoft explains why Windows remembers your USB drives after unplugging

Windows keeps records of USB storage devices in the registry (USBSTOR key) even after they are unplugged, because it cannot know if the device will return. Microsoft has documented this behavior since 2012, and Linux and macOS maintain similar device logs.

• Records live in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USBSTOR
• USBSTOR covers only storage drives, not keyboards, mice or webcams
• Entries hold device name, identifiers and dates, but not file lists
• You can check them with Get-PnpDevice -Class DiskDrive in PowerShell