Size on disk is about 64x less relevant than size in RAM for me. To give Zed some credit in this area, it's statically linked and the Linux binary is half the size as the Windows one.
It is Rust software, so there is probably a good 50-90% waste when it comes to just raw needed vs. actual lines of code in there, but there is no way anyone makes a renderer so overcomplicated that it takes up a meaningful part of the 500 MB or so Zed takes up on Windows.