Operational doesn't mean confidential. Sometimes reliability is the most important thing. For example sending a message to parents that school will be closed due to snow.
Reliably getting the message to the correct recipient?
I just have a bone to pick with all this software using phone numbers as ID or notifications. Send an email where we can filter it or if you must, do an app with notifications I can tune to my liking.
My kids’ school sends email, SMS, in-app, and phone (configurable by me, except for emergency notifications, which seem to either tree or hit them all).
SMS is almost always the one I see first, but they seem to use it as just one layer in a reliability sandwich.
Yes, there are a bunch of hoops to jump through if your businesses need to send out a lot of texts. If you have a 8xx number, there are even more strict rules.
For years, we were able to get away with email to sms addresses but they have become undependable as the carriers are blocking them more and more; likely because of the amount of spam going out.