In my opinion, a simple Table of Contents based on headings at the beginning of notes would be enough to address this issue.
Maybe many users want folders because they are more "visual" than searchers.
I consider myself a visual guy in this matter: I avoid putting too much stuff at a note because it becomes messy, then I found myself making new folders and tags to store small pieces of data and keep an eye on everything.
EN searches always give me tons of results, and that makes many of them useless to me, specially when I need to quickly find something. On the other hand, I'm fast in finding things if I visually know where I put them.
It might be a personal issue, since a lot of users are satisfied with EN the way it is today. I'm clearly aware of it.
Anyway, if I had a table of contents for headings in each note, my need for more folders/tags would diminish a lot, because my notes would be able to go as large as needed. Take a look at USA's wikipedia article: there is a huge ammount of data there, but yet it is pretty manageable.