I would welcome lightweight version of Code (no extension/git integration) as a Notepad replacement.
The extra tens of mbs of electron (zipped) is just because it is supposed to be easy to add those features and hack on it. Notepad needs nothing of that.
Heck, imagine what you could do in 4mb using only the things included in Windows. How large is notepad++?
edit: the minimal 64bit notepad++ is 5.8mb and the 32bit version is 4.5mb. That's so small compressing binaries or memory doesn't bring much.