The majority of game engines scene graphs are retained mode 3D abstractions.

Everyone thinks that they can do better with an immediate mode API, then we start building some kind of data structure to track down what needs to be drawn and when, with the result being similar to the traditional joke of half-implemented Lisp or ORMs, but applied to retained mode rendering.

Sure, some experts manage to get it right, and those are the ones that get to write AAA game engines, but many don't.