Then turn it off? Motion blur, TSR and auto-exposure are also both on by default and everybody constantly complains about them too.
Unreal has many dubious default settings. The defaults for auto-exposure’s histogram min is set way too high and pretty much guarantees the AE target will fall off of the bottom end in any remotely dark scene, meanwhile motion blur targets 30 FPS by default.
The default settings suck, that’s software for you.