The main difference is "IDEs" typically contain custom, ad hoc text editors in them. They don't allow you to build transferable skills that can be used to edit any text. People who use them will typically use some other editor to make documents, another one for their notes, and one per programming language.

I started using Emacs 15+ years ago because you can easily make it into an IDE, but it works for any text. Essentially it's like learning to use a kitchen knife vs buying a mincer, a grater, a food processor, a mandolin, and whatever other single-purpose tools they're peddling at the kitchen shop today.

Since then, the Emacs way has caught on. I see stuff like Atom and VSCode as just vastly inferior forms of Emacs. They can all be text editors or IDEs if you want them to be.