Video should explain everything: (had to upload one of videos Youtube due to 10mb limit):
Description Pay attention to Edges of where light hits & how there's lots of constant flickering
(2) Minecraft RTX issue - YouTube

Steps to Reproduce:

1. Enter a world with Ray tracing turned on
2. Set time to day and lock day-night cycle
3. Build a 10x10x10 Cube (or any other size, the point is to let light Leak into a building)
4. Destroy a block where sun is facing, make sure Sun light is coming in the building as seen in the video.
5. Look at the edges of where light hits.

Expected results:
There shouldn't be any flickering & there should be an Stable image

Observed results:
Constant flickering on edges of where light hits

It's also worth noting It appears pixelated and has some kind of Stair-like effect on it from specific angles, but even with those, an Stable image is expected.