I would bet that it's really in the single digit range. I think lots of programmers dishonestly claim to use it because its some sort of badge of honor to say you do.

Is more from old habits than a badge of honor. Fewer new developers use emacs or vi for coding. But I think "single digits" is too low too. I've been to talks by Microsoft engineers where they code using vi or emacs. One of the reasons is that the IDEs are always a step behind the languages.

> One of the reasons is that the IDEs are always a step behind the languages.

Depends on the language, some of them are IDE friendly, e.g. Java, C#, Eiffel, VB, Delphi, C++ Builder,

A lot of developers who use IDEs Ike Visual Studio also use VI style bindings with modal development styles within those IDEs.

When Visual Studio Code came out, the VIM extension was one of the most sought after.