Personally, I think that is possible. My guess is that godot translates/compiles the gd scripts into bytecode. (Also because the word "bytecode" occurs often in modules/gdscript/gd_compiler.cpp)
There exist bytecodes decompilers for other languages which work quite well. But I don't know of any which is available for godot. You could try a decompiler for python pyc. I doubt it will work. Decompiled bytecode will however not be the same as your gdscript. Comments will be missing and probably also the names of local variables/identifiers.
So most certainly you'd have to write your own gdscript decompiler (or adjust an existing decompiler to understand the gdc file format and tokens). :-) Probably re-coding your scripts is easier but I don't know the size of your project.