I don't get the nostalgia for NotePad - the most featureless piece of software ever invented.
I think it's the same reason I sometimes decide to leave the computer entirely and grab some pen and paper to really get things done.
I think there's little credit to be given here. A text widget is part of any gui toolkit and there are hundreds of notepad like text editors. I think basically every DE on Linux has their own...
There's been UltraEdit since 1994, SciTE since 1999, Notepad++ since 2003, the browser's address bar to remove formatting or just for holding some text...
Just like how almost everyone I knew used Paint.NET rather than mspaint.