Whether or not it is worth it to invest time into manually tuning ram depends on the user's usage scenario.

Example, I use my PC for games.

I have a cl17 4000 xmp profile. It doesn't give 240 FPS on max settings with an oced 2080ti in modern warfare. It fluctuates between 145-200ish. This isn't very good if you are trying to power a 240hz monitor now is it? Of course not.

I manually tuned to cl15 4000. Now my fps fluctuates between 190-270, sometimes higher for brief moments. Massive gains right?

Tell me more how it isn't worth investing time into tuning ram. It's based on usage scenarios, It's not black and white like you think it is.