Autocomplete, hinting, type checking, navigation, documentation display, automated refactoring, interactive debugging, and integration with other tools like test runners and databases, are some of the major features which yes, are indeed force multipliers.
This all becomes even more important when working on large codebases, and/or code you didn't write all yourself.
For reference: https://gitlab.com/datenstrom/home
Edit: just saw your response to the sibling reply didn't realize you included (enhanced) Vim in IDEs as I haven't heard of it referred to as one before, quite the opposite usually.
Although I will say that I've been using Vim a lot less since I started using VScode.
That looks like an awesome Vim environment though!
Refactoring is a good example: I’ve noticed that most programmers who don’t use advanced editors avoid fixing things which require analysis because it’s tedious to do right. That leads to accumulated technical debt over time with variables or methods having now-inaccurate names, etc. Nothing critical but a frictional cost which goes down when you have easy tools to perform language-aware refactoring (e.g. replacing a name in a function but not the same name used elsewhere in the same file).
https://twitter.com/ID_AA_Carmack/status/1302651878065475584
When writing well-contained code where I can easily understand external dependencies I could just as well use notepad. Emacs shines when I want macros or multiple cursors, interactive development (I am a schemer) at just general code navigation. When doing things that are not scheme I could probably edit code just fine in just about any editor.
The only things I really miss in other editors (probably because I never looked) are the features for jumping around. I can jump to a definition (across files) in 1s which sets a "mark" from the place I left. Jumping back takes less than a second. I could of course do it, but it was more involved and I couldn't do it without having to think and let go of what was in my mind at the time.
Anyway, you grow into your editing style. A friend told me he would likely get seizures by developing like me.
Better be proficient in command line tools and a simple editor than not being proficient in an fancy editor.
But once you are used to the fancy editor it can be very efficient to be able to lookup a definition, do some refactorings, get an code outline view, auto completion, editing helps (text templates or the automatic } and indention) etc.
Being able from the same interface to visualize your database and state of the program is also good !