For any Windows 11 user that does not known, ‘optional updates’ are the ones used for device drivers like GPU cards, sound cards and other peripherals you may have connected to your Windows 11 system.
As Windows Report points out, this is not needed for the correct functionality of Windows 11 (hence optional updates) but may increase performance and/or stability of the system overall so is worth enabling. Please continue to read to see how it’s down.