I've been overclocking since the late 90s with the infamous first monster overclocker that everyone could get their hands on, the Celeron 333MHz->450MHz. Over the past nearly 20 years (holy cow has it been that long?) slowly evolving from a 1280x1024 monitor to a 2560x1440 monitor, I have noticed that overclocking the CPU offers diminished returns in gaming performance.
Today it's more about GPU performance, especially overclocking GPU performance. Like someone said above, it's no longer worth the heat and power increase that it used to be. Overclocking a GPU is where the real game performance increase benefit is. On the other hand, productivity applications like video rendering can benefit from a CPU overclock quite well...about the only thing I ever find myself cranking my 4690K up to 4.7GHz for these days to speed rendering time up.