Twilio is frequently
aggressive with describing how much work integration is. Literally, yeah, you can ring a phone in one line of code but you
really don't want to. It starts getting powerful when you can push full features - tested, with UI/UX, production-ready - in about a day, and you could write a telephony business in about a month, from scratch. Those aren't exaggerations in the slightest.
See my upcoming free guide on productizing Twilio apps for why using the sample code in a live environmwnt is almost always a vewwwwwwy bad idea.