Ooh! This is a great question!
I think that GraphQL is not a REST killer. It is a REST saver. It shouldn't be the things that replaces your REST API, but rather the thing that sits in front of it and keeps you from having to change it all the time just to get the right data in the right format to your front end. In other words - it's the thing that is going to keep you out of technical debt.
I wrote about this just this week along with some video tutorials for anyone out there who is new to GraphQL like I was and wants to understand how it fits into the applications they have today.
medium.freecodecamp.org/why-graphql-is-the-key-to…