I'm not sure how the Galaxy handles it but if it's similar to the stock android situation, you're likely often only seeing a 60hz screen rate. You can go to dev

I'm not sure how the Galaxy handles it but if it's similar to the stock android situation, you're likely often only seeing a 60hz screen rate. You can go to developer settings (or perhaps screen settings) and force 90hz or 120hz on. If your eyesight is otherwise good (especially if your younger than 50) you should be able to notice the difference quickly.