I'll be in the middle of coding and my phone goes off, so I stop everything I'm doing to see that my monthly was autopaid. With email, I check it every 2 hours to minimize distractions and I can also use filters to ignore certain routine emails, but companies text messaging me feels like an intrusion into my privacy.
2) [Almost?] all companies let you opt out of text message notifications and/or customize it, I've never seen a company that didn't. For example, for Verizon I just go into "Manage your communications and alerts" online and set it to "email" rather than "text." Phone companies set text by default only because they already have your phone number.
3) Assuming you don't have a dumb phone, this is a solved problem, just put your phone on "do not disturb" while you are working. You can set it to where priority numbers (like your spouse) still give you notifications for emergencies. You can even set "do not disturb" to automatically coincide with your calendar events and/or time of day.
If you're checking email every 2, texts should be every 4. If you're getting urgent messages over text often, someone else is making a mistake. Most people I know don't even read texts for hours later.
> Text message should be used only for time-sensitive communication
That's how I use it as well, but I'm not sure we're in the majority. To the phone company, a text message is the less time sensitive way to communicate. Time sensitive communications are handled with an actual phone call.
So, like the parent of your comment, I find that email is a much better medium for non-time-sensitive communication than SMS.