> But why would I care about how the engine works? It should just work, I don't want to waste my time with understanding how.

Either this is sarcasm or you need someone to educate you thoroughly.

How the engine works is fundamental to understanding what you can and cannot do as a game programmer, severe pitfalls and above all: where areas for innovation exist for your specific type of game.

I make racing games for example, you might be surprised to learn that if I ignored my engine then it would be impossible, because my engine (Unreal 5) is not very good at handling extremely fast moving objects in the world. It puts enormous stress on the level-of-detail system. I need to understand that otherwise my game won't work.

What you said is as silly as saying "I'm making an apartment block, why do I need to understand the properties of bricks? they should just work!"