i'm sure there are reasons for this, and it must have been discussed before, but why is the game developed in such a hodge-podge manner? im not trying to be disrespectful of the developers, but I'm just trying to understand if there are "historical" reasons why we're stuck with so many different programming paradigms, or is there actually a reason for it?
It's a very typical thing for game developers to do. Jbeam can be discounted since it's not a programming language. Lua is a scripting language, commonly used in AAA games, as well as BeamNG. It provides developers the ability to create additions to the game with ease. I'm guessing by Java, you mean JS (JavaScript). It's used in the UI since HTML is pretty capable to do UI things. In the end, it just makes things easier
Every language has their usage. Writing everything in one language does not mean it is better. We use C/C++ for the parts that need performance. Lua for the easy-to-change parts that represent mods and gameplay to keep the integration time low. JS/HTML because that is the tech our UI framework uses.