Texting is awesome for times where you don't need the social entanglements a full conversation entails but you do need to quickly give someone information or ask a question. You can also text in many situations where voice calls aren't possible. Sometimes you just don't want to speak to someone but are forced by cirumstance to interact with them.
Texting is unquestionably useful, it's just that people take it too far and communicate almost exclusively through it or do dumb shit like text in the car while driving or in the movie theater. I text all the time and it's rarely frivolous shit about what I had for lunch (stir fry). It's also huge in the business world these days.