It's time for people to move on from Emacs. Development effort would be better spent on lightweight editors that complement modern IDE editors (e.g., the Java editor in Eclipse).
I don't get what you mean by "moving on". Just because people started writing Emacs 30 years ago does not mean the code is crufty and old. Both Emacs and Vim work well with all modern desktop environments on all major operating systems. I don't see why anyone should be "moving on".
You might love your IDE, but many people hate them. Some of us don't like bloated software with features we don't need or use.
(I'm a Vim user, BTW :) )
Here's one. I only make 2 minor additions (no customizations) to the default key bindings. By now, the defaults are pretty much hardwired into my hands.
There is code to support each platform and windowing system emacs runs on. There is support for managing buffers, and other very primitive editor functionality like that. Then there is the Lisp VM and associated data structures ("Lisp_Object") to glue everything together. On top of that are some primitive functions ("and", "cdr", etc.), along with some primitive editing functions ("next-line") implemented in C. That's about it; the rest is all Emacs Lisp code that you can simply choose not to run. (Yes, some gets compiled right into the Emacs binary to speed startup, but you can skip that.)
Sure, you can argue that many emacs extensions (hello, Gnus) are bloat. But you can just pretend it doesn't exist; nobody is forcing you to use anything. Plain emacs is a very simple toolkit for building your own editor. Emacs with simple.el (and friends) is still a very simple, but rich, text editor. As you add packages, you add functionality and complexity... but you can choose what to add, Emacs is infinitely malleable and does not care what you do to it.
I am not too familiar with Eclipse, but I doubt that it is simpler than Emacs.
There's no such things as an editor that works the way you like unless you only have very basic text editing needs. This is where people generally resort to Notepad or Word.
In the other case you really want a good editor that fits both your fingers and thinking, and that's where you had better write the editor yourself. It is at this stage when many people have figured out that starting with Emacs is the easiest path.
Emacs is a lifestyle. Embrace it.
Extending Emacs or Vim to work seamlessly with your programming language is, IMO, a much smarter move than building an IDE from scratch.
That's the problem. GTK doesn't work very well on the Mac, and (AFAIK) there's no GTK+ on Haiku. OTOH, Emacs works perfectly on both platforms :)