Even so, lots of people find emulators useful, especially in the context of an IDE that brings its own compelling features to the table. For years I used a commercial emulator in Visual Studio that was a huge boost to my productivity. It was the work of a sole developer.

And smalltalk does bring a lot of compelling features, as others here have noted.

(And some emulators are quite good, like evil-mode, which has converted some hard-core vimmers. Which also makes me wonder about implementing the core of emacs in smalltalk, making similar functions available, and extending it with smalltalk instead of elisp.)