It has nothing to do with Unity. Unity code is just compiled into IL byte code which is then run by JIT compiler on player machine or when using il2cpp runtime IL is converted to C++ code which is then compiled into native code. Ren'Py games are just written in interpreted language (an extension of Python language) but it's also barely even an engine. OoT doesn't have game scripts hardcoded, we made our own scripting language and all scripts are written in that language and they are in plain text files in
SCRIPTS~
folder. That folder is bundled in Android version in
textfiles
bundle but the code for loading scripts is shared between desktop and android versions, so if you put
SCRIPTS~
folder next to
Assets
folder in the public game folder then OoT runtime will load scripts from there instead, you will just have to manually update that folder from desktop version, since android game installers only update bundled content and raw script folder has higher priority when loading scripts.
Here for example latest scripts (but it still requires full game to be installed to run). As you can see it's plain text files.