[nadam]

You choose C++ to be able to control performance more than in lots of other languages. In a game engine or other very performance intensive software, people tend to think a lot about memory management. Whether in very rare cases, for a part of a system the optimal solution is something similar to a garbage collector: this might be possible, but quite irrelevant, because the important thing is not the final solution, but the fact that you can (sometimes quite creatively) control and constantly fine tune things, so that you can come up with an optimal solution.