Thanks everyone for your input!
-Omar, all my textures are 4K and downloaded from PolyHaven. But I’ll try putting everything into a new blend file and see if that affects anything.
-Martin, I don’t think so? I’m still learning blender and haven’t even touched the compositing nodes yet. And the pixelation occurs even with the default 1920 x 1080.
-Adrian, Here is a Dropbox link to the blend file.
I really appreciate the help everyone:)
