I would say technically no, but if there was a job or something which required a 'clear voice' and if the impediment was severe then I am sure it would impact the person's success. US President Biden speaks with a bit of a stutter, but I think you can say he speaks clearly.
If you tell someone something loud and clear, you are very easily understood, either because your voice is very clear or because you express yourself very clearly. Lisa's voice comes through loud and clear. Spoken english training in Aurangabad
I would like to reply first that concerning telephone work like in call centres we do not shout so not loud voice and secondly, how can the sound leaving our month be clear if it is interrupted and repeated by a stutter?