As the old saying goes, "emacs is an operating system lacking only a decent text editor".

Not so. Evil mode is a great text editor.

Ha, fair. Lightweight in this context is relative to Notepad or any modern Windows application.

Notepad.exe used to be <200kB. Emacs is tens of megabytes

Notepad was just a wrapper around some default win32 controls. Judging alone by exe size is not right, although probably a “statically linked” notepad would still be smaller than emacs

It is right by definition. Link emacs to those controls, shed some statically linked weight, and it will also become lighter!

To be fair you can say that of anything with a scripting engine, you could have all that in vim or stripped down emacs

Anything with a scripting engine isn't lightweight compared to (classic) Notepad!

(Also, a lot of that stuff comes bundled with Emacs out-of-the-box, further disqualifying it. Having a scripting engine is one thing, but having a scripting engine along with the whole rest of the jet is something else entirely!)