But not every game does have those, which is why they must be coded. How else does the system be flexible enough to make either a 3d fps or a Bejeweled puzzle game from the same API?

I generally agree with you btw, but I think it's just a matter of course.

I tried gdevelop before and I think it's the closest thing to what you might be looking for. You can make a sprite, then give it the "player movement behaviour", get a box and give it the "mouse draggable" behaviour. Etc.