with all this talk about fps, can somone explain why is 144Hz such a big deal compared to 120Hz? like, the difference between them is so small. does it actually make a difference in practice?
It's not a big deal vs 120Hz really. The main advantage 144Hz has is that it can do 120 FPS with VRR.
Now you might think: can't 120Hz do 120 FPS?
Well it can, but that's outside the VRR active range.
With VRR, the upper range is about 116 FPS on 120Hz before you start getting input lag from multiple frames being queued up. This limit is around 138 FPS on 144Hz.
Now 116 FPS vs 120 FPS is negligible. Nobody should be able to see the difference because they are so close.
But there are cases where a game is only smooth when running at exact multiples of 30 or even 60.
116 FPS
should be perfectly smooth; but if it's a game where the camera updates at multiples of 60, it will be juddering constantly.
So you have to choose between 120 FPS with a couple of frames of input lag, or 60 FPS without any.
In other cases, the choice is a bit easier if it's smooth at multiples of 30 or 50, because then you can limit to 90 or 100 FPS - which are still a lot better than 60.
It has irritated me somewhat that most PS5/XS games do not let you just turn off VSync if you have a VRR display. Not that I'm expecting Nintendo to reach that dizzying height either!
VRR still requires v-sync to operate correctly.
Without it, you'll see screen tearing at the upper end of the range, as the frame rate approaches the maximum refresh rate - or even further down in the range if frame-times are highly variable.
To be fair they could be telling the truth - I struggled to tell the truth between 60hz and 120hz on my LG C3. Diminishing returns and all that.
I expect there must be something else at play, because 60 to 120 FPS is very far away from diminished returns.
Many people start to report that 240Hz vs 360Hz is a relatively small upgrade - but then find that 480Hz/500Hz is a noticeable upgrade over either of those.
It's more that you need to double the frame/refresh rate once you get above a certain point, rather than the difference not being noticeable.
But it's also important to note that refresh rates by themselves do very little.
60Hz vs 120Hz or 240Hz does almost nothing if your game is running at 60 FPS.
You really only get better input lag from it (60Hz refreshes are 16ms apart, 240Hz are only 4ms apart - so the screen updates 12ms faster).