This proposal is always loudly shouted down by teachers and textbook authors who want to keep things simple and consistent. While I'm sympathetic, I think they've been going about it the wrong way.
I don't care deeply about fmap=map, but I am opposed to preserving the prelude in amber for teaching purposes.
Instead, I believe the teachers need to create their own requirements for a beginner's mode, and that we add long-term support for that with a few widely-published features.
For example:
{-# LANGUAGE BeginnerMode #-}
import BeginnerPrelude
plus a web page at
haskell.org that every author could point to that would detail any changes.
Any book could remain relevant simply by updating a page linked to this site with relevant updates. These might include changes to the BeginnerPrelude as well as current help on transitioning from Beginner to the current full prelude.