Exactly the same steps and situation for me as BrianZhang.

I'm also seeing this in the Canvas SwiftUI Previews, iMac (Retina 5K, 27-inch, 2019), macOS Big Sur 11.1. Just building the Apple 'Landmarks' Example and seeing Yellow regions all over the place, iPhone 11 Pro simulator. Is there a fix?

A long time ago, but I'm seeing the same issue with Unity 2022.3.2f1 - did you ever get this working?