Posting from Github:
Similar to the “Mail is Owner” feature that sends emails from different senders who are owners of the contact, I think a similar feature should be for SMS.
This means if a sales rep is the contact owner, a single SMS message send can appear as though it came from that individual.
SMS is very effective and this would create a more personalized experience.
For this to work Users/owners should have a phone number field. Then if the setting for SMS is set to “SMS is Owner” it should function exactly like the current mail feature.
Original issue: https://github.com/mautic/mautic/issues/7530