Oh my, this is an anti-pattern and equivalent to (on a single *nix machine): “I give myself the UID 0, aka root, because I can’t be bothered to figure out what permissions exactly are required”. I mean’ just look at it in the docs. With this command, the current user, that is, you is made superuser or in other words:
Allows super-user access to perform any action on any resource. When used in a ClusterRoleBinding, it gives full control over every resource in the cluster and in all namespaces.
Why does Google think this is necessary?