Why would they be forbidden from giving a name? .GRC , you have a point. First thing I ask is 'Who am I speaking to?' It can save time later, when I get passed around the system or have to ring back, only to find I've got someone else, who hasn't the faintest idea of what has been said or done or what I'm referring to.
Tthey can always use a work name rather than their true one.
There's no legal obligation.You can still sue the company using anything done or said by them in the course of their employ, whether they give a name or not !