As long as you are required to have an active Steam account to play the games you purchased on Steam, an account that can be revoked if you break the terms and

As long as you are required to have an active Steam account to play the games you purchased on Steam, an account that can be revoked if you break the terms and agreements, then it is a form of rights management. The simplest form of rights management it has is that it will not allow two simultaneous connections to the same account, regardless if you have nothing but DRM free games in the account.