If you’re running an RTX Card there really isn’t any need to up the stock graphics level.
I run a GTX 1080 card on a 4K TV at stock settings and couldn’t be any happier with the graphics.
With an RTX Card id be more inclined to look at your TV. All 4K TVs are not created equal as far as display quality. It could very well be the refresh rate on your TV. I use a Sony 49” with a 240 hZ refresh rate. 4K TVs come in 60, 120, and 240 hZ. The motion flow is better the higher the number.
That could be your issue. Good Luck,