This is false.
Give your friend this web address:
scanningbacklight.com/references
For many people this may be true, but do not forget "input lag".
Rendering more frames means frames are fresher when finally delivered to the display.
60fps means frames may be 1/60second stale (16ms).
120fps means frames may be 1/120second stale (8ms).
240fps means frames may be 1/240second stale (4ms).
At 240fps instead of 60fps, your display gets a frame that's "12 milliseconds fresher" (16 - 4 = 12)
(frames rendered only 4ms ago, not 16ms ago.)
That means you can see enemies sooner. React sooner.
That's a HUGE advantage in competition gaming!
Even if you can't feel it!
Competition championship online game --
ONE MILLISECOND CAN MATTER
When two people shoot at the same time in a video game,
The person who shoots first wins!
Reacting 1ms sooner means you win the trophy prize in the pro competition championship!
Even if you CANT feel the millisecond!
It's like winning the 100 meter Olympics sprint -- tiny amounts matter.
THEREFORE, It's not "necessarily" a waste to have fps > Hz and fps > 60 even if you can't feel it.
(Even though, in fact, one can feel the difference between 60fps@120Hz, and 120fps@120Hz)
Also, AnandTech has a
good article about input lag.