Hmm, there are mosly small improvements but:Other than the cameras and 5G radio, what can the iPhone 12 Pro do that my iPhone X can’t? I’m trying to be open minded to an upgrade, but I can’t find a reason to.
-Bigger Screen
-More powerful a14 chip
-Lidar (I guess it's part of the camera but it's a sensor)
-Slightly bigger battery = Better Battery life (actually a downgrade from the 11 Pro, but an upgrade over the X)
-Stronger front glass
-More water resistant
-MagSafe
-More Storage
-Better contrast ratio
-Brigther Screen
-Dual sim
-Ultra Wideband chip
I wouldn't upgrade from a X as I do consider these changes to be quite minor, but coming from a 7+, there are quite a lot of improvements for me.

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But youtube videos are capped at 60 fps. You can't get 120 on YT, so between those 2 screens. There will be very very little differences for most media consumption. 120 fps is good at games and scrolling.120hz is better for watching video...movies as you get smoother looking picture. It is "refreshing" the image on the screen 120 times per second as opposed to 60 times per second. Downside is that it uses more power...shorter battery life between charges unless you increase the battery size (capacity)...bigger device.