Per Sarai's suggestion:
It would be really helpful if we added some configuration to the Default MenuItem, so users could try out its props: such as the ability to make it disabled, editing its label and description, removing or selecting a different icon (like with Button), removing or adding a thumbnail, and try out hideDescriptionOverflow.
Let's build a configurable demo for MenuItem to enable users to test out different props. If possible, we could remove some of the separate demos if we think the configurable demo sufficiently covers them.