Neither on emacs and nor it’s a Mac first app. Probably the most misleading app name ever.

It isn't compatible with TeX/LaTeX but it does serve the same purpose (and converters are available). I don't disagree it's a weak name, though. The naming implies some sort of rich LaTeX editor plugin for emacs - I need Mike Meyers to leap out and say "Texmacs is neither LaTeX nor Emacs - discuss."

The name alone is hilarious bad.

I'd never heard of it but when I saw the title of this post I practically tripped over myself to click it. Latex and Emacs! From GNU!! How have I not heard of it?

A few lines in to the page. Oh it's nothing to do with either of latex or Emacs.