With One UI 6 and still in One UI 7 for whatever reason, the animation when closing an app where the others come forward to fill it's place has gotten a lot more stiff.
Closing an app in the app switcher causes the apps behind it to come forward, but they currently move at a constant velocity and suddenly stop when they reach the destination.
One ui 5 and older had nicer flowing animations in this regard so I'd encourage the revival of that specific animation.
