A:Answer It is my understanding that there are no 4K screens that have a refresh rate higher than 120Hz today. The Sony OLED (the A1E is OLED) screen is actually made by LG, and their screens have the same refresh. Mfrs deliberately confuse us with marketing info that tries to lead us to believe that they have higher refresh rates, and their software does work to try to do this, however, the actual physical refresh capability of 4K TVs is limited to 120HZ, and there may be less expensive 4K TVs that still offer 60Hz capability. As do other manufacturers, Sony promotes its proprietary "Motionflow XR 960" technology and tries to equate it to a high refresh rate, but if you look in detail they will show that the screen refresh is 120 Hz and that their Motionflow is their "special sauce" software that seeks to eliminate or reduce motion blur. But the actual redrawing of the screen happens only 120 times per second.
This is a very technical area, that is hard to reduce to an easy soundbite. How the brain interprets motion is complicated and simply doubling the refresh rate actually does not improve the perception of motion on the screen.
There is a great article by C-Net on 4K refresh rates, which goes into a lot of detail - look for it on the internet if you need more info.