When needed, even today programmers achieve high efficiency levels. As an example, look at John McCarmack's write ups about the first oculus headset they develo

When needed, even today programmers achieve high efficiency levels. As an example, look at John McCarmack's write ups about the first oculus headset they developed. It was supposed to run entirely on Galaxy S7 phones. They had to devise an overclocked mode for the screen to be able to maintain a consistent 90Hz in order to avoid nausea. I used the Gear VR and it was true that no matter what content was being displayed, the headset never lagged or fluctuated. Really impressive considering it is only now that flagship phones have started offering 90Hz and 120Hz screens.