One of the neovim devs released a video just a couple of days ago on the topic.
He suggests neovim (and vim, emacs etc) fall into a category between text editor and IDE.
The term he uses is PDE (personalised development environment). In short, you have lots of power to customise your setup; you can give it some IDE-like behaviour but the way you do it tends to be by making personal choices of plugins and config.
It's not just a text editor, it's definitely not 'integrated'. I'm inclined to agree with him.
https://youtu.be/QMVIJhC9Veg