Admin -> Run Updates, Unresolved dependency
So what am I missing?


Nothing at all, the messages are pretty clear:

The version of CKEditor Media Browser that you're updating to has a dependency on File Entity 7.x-2.0 or greater. You have version 7.x-2.0-beta3, which is not greater than 7.x-2.0, so the upgrade isn't possible.

You need to update File Entity to the required version first, then proceed with the update of the media browser module.

Do bear in mind that the modules you're dealing with are in beta, and haven't had development effort in a while. It's entirely possible that you might not be able to perform the update. Case in point: https://www.drupal.org/node/2838674