If your Windows 10 is slow to boot after an update, it may hint that there is an incompatibility between the latest Windows update and your computer drivers, especially the graphics driver. The newest driver may provide better compatibility with the recent release of Windows 10. Therefore, it's also worth trying to update the graphics driver on your computer.
Step 1. For the same, right-click on "This PC" and go to "Manage", and then choose "Device Manager".
Step 2. Now expand "Display adapters", later right-click on the graphics card driver, and select "Update driver".