Google is a huge company. You might wonder what that has to do with anything, but ... after years of frustration let me just state with absolute certainty: Wit

Google is a huge company. You might wonder what that has to do with anything, but ... after years of frustration let me just state with absolute certainty: With VERY few exceptions (like, say, the build system or some backend infrastructure) EVERY Google project has essentially it's own private structure, base libraries, framework and things that look extremely close ... aren't really. Also, even components of the same app don't use the same framework throughout. It wouldn't surprise me if it wasn't just the case that Docs and Sheets aren't written in the same language but that the drawings you can embed in both are implemented in yet another language.