>Why on earth would I ever want to use SQLite if I have access to a sufficiently advanced code generator which can generate me a similarly high quality database system

https://www.youtube.com/watch?v=V_qzqY1bb7I your sufficiently advanced code generator may generate you a high quality database system for some measure of quality, but it will not have SQLite's reliability over the extremely long tail of edge cases proven through its testing and use in real life