Old job we used to send SMS out from RepairShopr. Job completed, requiring approval, reminder to collect etc. Would always try calling first then follow up with a SMS if no answer.
It's the "bulk" part, not the texting part, that's the issue. Bulk texting, mail, email, etc., tends to be nothing but an annoyance.
Status updates are generally welcome, and only occur if/when needed, and really aren't normally sent out in bulk, but to specific clients for reasons that they understand why they're receiving them.