Another Emacs user here. I would argue that even Emacs is a bit of a struggle sometimes. More modern editors like Sublime Text, Kate, or even Notepad have an advantage of being intuitive. Typing on a letter always outputs that exact letter. The shift key does one thing and one thing only. Mouse integration allows for rather precise cursor placement in a way that utilizes a human's natural hand-eye coordination. The shortcuts that they do use are common across the OS (no need to remember if the copy you need is Ctrl+A - W, Ctrl+W, Ctrl+Shift+C, or Ctrl+C).

Part of the issue is that operating systems have gotten more advanced and more standardized since Vi and Emacs were originally built. However, there is the case that UI designers have learned a lot over the decades. I like Emacs as well, especially when I am doing sysadmin work. However, I have to admit that it is not always intuitive. And even Emacs is more intuitive compared to the modal-nature of Vi.