You're mostly right though but it's not really about the most performance i'm after since 1200fps+ is really usefull it the latency in online fps, especially fortnite where input lag matters the most. You'll get more out of a good cpu/ram oc but the os nontheless manages your games and having it running 20 processes in the background sure impact on how quicky your game input is managed by your system. I can assure you i'm very sensitive to input lag and if you have ever played fortnite on a semi-pro level you would understand the intricacy of input lag and how much the outcomes differ with or without it.Super stripping the os has very little affect on the system running. It just starts to break things and really in the long term not providing any benefit.
Just an honest opinion and no offense
Anyway , what you say is best advice for begginers and people than aren't ready to dig a little deeper in the os without beeing scared to maybe reset the cmos and resinstall the os 50 times before getting it right.
I learnt the most doing mistakes and i keep getting better
