In my uni, many professors used Emacs when demonstrating. For example, one course [0] used the Agda language [1] as a proof assistant. Afaik, the only good interactive Agda interface is the Emacs Agda mode [2]. Maybe you just live in a region of the world that happens to have a weak culture of using Emacs?

[0] http://www.cse.chalmers.se/edu/year/2017/course/DAT350/

[1] https://wiki.portal.chalmers.se/agda/pmwiki.php

[2] https://agda.readthedocs.io/en/latest/tools/emacs-mode.html