e-Messaging - Is it possible to remove user and role?

Actually this is for most of the emessaging objects like Outbound Profile, Inbound profile and gateways etc.

You can deactivate some of the objects but cannot completely delete them.

There might be relations in records in database which does not allow for deletion, that's why delete is not available and only deactivation is available.

For example, if there are records in outbound message table for a particular profile, it cannot be deleted till references are there. This is true for most of the objects.

In a nutshell, delete is not available.
UPDATED:  March 23, 2017