In response to Nick's point 4: To me, these are important aspects of 'in the stdlib'.

First is having issues on this tracker.  As Guido said in his King Day speech, non-trivial software is a collective project.  IDLE needs continued access to dependency experts, such as Serhiy for tkinter, and platform experts, such as Ned for Mac.  In April, I nosyed Kristján Valur Jónsson to ask an IDLE question that seemed related to a socket patch he pushed, and he helpfully answered.  On the other side, users are much more likely to participate here than on a separate tracker.

Second is being easily installable with the rest of Python.  I think some out-of-the-box augment to the console is crucial on Windows.

I am aware that Linux distributions have a separate tkinter-gui install instead of just a checkbox option.  I think it should consistently, on all plateforms, comprise _tkinter, tkinter, idlelib, turtle, and turtledemo.

All of those except idlelib are documented even though optional.  So I think idlelib could be also.  But documenting direct usage, which Nick recommended in #24225, could be relegated to the modules themselves and the idlelib README or a new text file.  Ditto for indicating replacements for thing known or strongly  suspected of external use.